WorldWideScience
1

Studies of crystalline CdZnTe radiation detectors and polycrystalline thin film CdTe for X-ray imaging applications  

CERN Document Server

The development of a replacement to the conventional film based X-ray imaging technique is required for many reasons. One possible route for this is the use of a large area film of a suitable semiconductor overlaid on an amorphous silicon readout array. A suitable semiconductor exists in cadmium telluride and its tertiary alloy cadmium zinc telluride. In this thesis the spectroscopic characteristics of commercially available CZT X- and gamma-radiation detectors are established. The electronic, optical, electro-optic, structural and compositional properties of these detectors are then investigated. The attained data is used to infer a greater understanding for the carrier transport in a CZT radiation detector following the interaction of a high energy photon. Following this a method used to fabricate large area films of CdTe on a commercial scale is described. This is cathodic electrodeposition from an aqueous electrolyte. ...

2001-01-01

2

X-ray diffraction evaluation of the structural perfection of cadmium telluride single crystals  

Science.gov (United States)

A high degree of structural perfection is an essential requirement for CdTe crystals used as substrates for the epitaxial growth of CdHgTe alloys. Here, a method for the evaluation of the structural perfection of CdTe crystals is proposed which is based on X-ray diffraction measurements using both two-crystal and three-crystal diffractometers (differential version). The method makes it possible to obtain more information on structural perfection both at the crystal surface and within the crystal body.

1988-08-01

3

Phase diagrams  

International Nuclear Information System (INIS)

The description is presented of binary phase diagrams of titanium alloyed with the following elements: silver, aluminium, arsenic, gold, boron, barium, beryllium, bismuth, carbon, calcium, cadmium, cobalt, chromium, copper, iron, gallium, germanium, hydrogen, hafnium, indium, iridium, potassium, lithium, magnesium, manganese, molybdenum, nitrogen, sodium, niobium, nickel, oxygen, osmium, phosphorus, lead, palladium, platinum, plutonium, rhenium, lanthanium, cerium, preseodymium, neodymium, gadolinium, erbium, terbium, thulium, lutetium, rhodium, ruthenium, scandium, silicon, tin, strontium, tantalum, technetium, thorium, uranium, vanadium, tungsten, yttrium, ytterbium, zinc and zirconium.

4

Anodic oxide coatings on metals and anodic protection /2nd revised and enlarged edition/. Anodnye oksidnye pokrytiia na metallakh i anodnaia zashchita /2nd revised and enlarged edition/  

Energy Technology Data Exchange (ETDEWEB)

The theoretical principles underlying the formation of oxide and, in particular, anodic oxide coatings on metals produced by chemical oxidation, anodizing in solutions, and anodizing in cold plasmas are reviewed. The mechanisms and conditions of anodic oxidation are described, and the structure of anodic oxide coatings on aluminum, magnesium, beryllium, zinc, cadmium, iron, cobalt, nickel, titanium, zirconium, tantalum, and chromium alloys is examined. Attention is also given to various applictins of anodized coatings. 54 references.

1985-01-01

5

Influence of alloying elements on the irradiation hardening and environmental sensitivity of zirconium alloys  

International Nuclear Information System (INIS)

Ten different alloys of zirconium have been tested with regard to the effect of irradiation on their mechanical properties and their sensitivity to environmentally induced failure. Two different environments were used: iodine vapour and liquid cesium with an addition of 2% cadmium. The neutron dose was 10"2"1n/cm"2 (E>1MeV) and the irradiation temperature was about 300 degrees C. All alloy additions increased the irradiation hardening. Especially notable was the large effect of titanium and tin on irradiation hardening. A limited amount of transmission electron microscopy was carried out in order to find an explanation to the effects. The testing in different environments showed that there is no clear correlation between environmental sensitivity and yield stress. For materials of similar yield stress an alloyed material tends to be more sensitive to environmental cracking than a material which only ...

1991-08-25

7

Trace metal characterization of the U-Al matrix by atomic spectroscopy  

International Nuclear Information System (INIS)

Uranium-aluminum alloys with a significant enrichment of uranium with "2"3"3U or "2"3"5U serve as nuclear fuels in research reactors. The quality assurance of this fuel requires, among other things, precise knowledge that all trace metal constituents that affect neutron economy, fuel integrity, and fuel fabrication process parameters are well within the specification limits. Trace metal characterization of "2"3"5U-Al alloy has been carried out by atomic spectrometry. The trace metal constituents of interest are grouped into common metals (silver, boron, calcium, cadmium, cobalt, chromium, copper, iron, magnesium, manganese, molybdenum, sodium, nickel, lead, silicon, tin, titanium, vanadium, tungsten, and zinc) and lanthanides (cerium, dysprosium, europium, gadolinium, holminium, lutetium, samarium, and terbium). The elements yttrium and zirconium are grouped with the latter in view of the chemical separation procedure used. ...

9

Reduction of cadmium toxicity to green microalga Stichococcus bacillaris by manganese  

Energy Technology Data Exchange (ETDEWEB)

Investigations of cadmium toxicity to microorganisms are now more concerned with the interactions of cadmium with different environmental factors and other metals. The interactions are complex and have not been thoroughly studied yet. Metal interactions may assume the form of synergism characterized by increase in toxicity, but also of antagonism in which one metal reduces the toxicity of another. Apart from cadmium interactions with such toxic metals as mercury and lead, interactions of cadmium with the essential trace elements seem to be very interesting because it has been assumed that algal cells take up cadmium by the system transporting these elements. A previous study showed that cadmium transport into Stichococcus bacillaris cells was inhibited by Mn/sup 2 +/ ions. Thus, it can be supported that there exist some possibilities of using those ions ...

1988-12-01

10

The method for iron removal from cadmium in the course of refining process; Sposob usuwania zelaza z kadmu w procesie jego rafinacji  

Energy Technology Data Exchange (ETDEWEB)

The pyrometallurgic method consisting in introduction of refining agent into the liquid cadmium has been presented. The refining agent consisting of silicon nitride, carbon dust and sodium hydroxide has been added in several portion into the liquid cadmium. Iron has been removed from the cadmium surface in the form of floating slag.

1992-10-30

11

Testing of solar cells for communication satellites  

International Nuclear Information System (INIS)

... cadmium sulfides communications electrons performance testing physical

12

Pyrolysis of dichlorodithiourea cadmium(II)  

Energy Technology Data Exchange (ETDEWEB)

By means of infrared spectroscopy, x-ray diffraction, and differential thermal analysis, the authors investigate the pyrolysis of dichlorodithiourea cadmium, the vapor phase epitaxy of the cadmium sulfide film, and the composition of the solid and gaseous pyrolysis products. Those products are found to include the thiocyanates of guanidine, ammonium, and hydrogen along with cadmium oxides and sulfates and hydrochloric acid.

1987-02-20

13

Electrochemical Solar Energy Converter  

International Science & Technology Center (ISTC)

Elaboration of Electrochemical Solar Energy Converter Incorporating Cadmium Selenide Semiconductor Developed Electrochemically

15

Thermal-neutron capture cross section and resonance integral of americium-241  

International Nuclear Information System (INIS)

The thermal-neutron capture cross section (#sigma#_0_,_g) and the resonance integral (I_0_,_g) leading to the ground state of "2"4"2Am were measured by an activation method for neutron capture by "2"4"1Am. A method with gadolinium, which was similar to the cadmium difference method, was used to measure the cross section #sigma#_0_,_g with attention to resonances of "2"4"1Am. Americium chloride samples containing "2"4"1Am radioisotope were irradiated for 68 h in the long-irradiation plug of the Kyoto University Research Reactor, KUR. Wires of Co/Al and Au/Al alloys were used as monitors to determine thermal-neutron fluxes and epithermal Westcott's indexes at the irradiation positions. An #alpha#-ray spectrometer was used to measure the activity ratios of "2"4"2Cm to "2"4"1Am. On the basis of Westcott's convention, the #sigma#_0_,_g and I_0_,_g values were determined as 628#+-#22 b and 3.5#+-#0.3 kb, respectively. (author)

2007-12-01

16

Development of pyro-separation technology based on molten salt electrolysis  

International Nuclear Information System (INIS)

In order to effectively recover uranium, rotation speed of solid cathode was examined, and effect of uranium concentration and current density on electrodeposition were confirmed. And the potentiostatic and galvanostatic electrorefining experiments were conducted. Element used in the experiments were Zr, Nd, La chlorides. The reduction potentials of chlorides metals on liquid Cd cathode were measured by cyclic voltammetry experiments. The electrowinning experiments were performed in order to recover small amounts of uranium in salt. Experimental set-up for the batch type reductive extraction experiments were developed and installed. On the base of experimental results of batch type, multi-stage extraction equipment was set-up, and optimum number of stage and recover yield were measured. In the oxidative extraction study is examine selective separation behavior of the rare earth metals from alloy composed of actinide and lanthanide metals to determine the effective ...

2010-10-01

17

Photocatalytic hydrogen production from solutions of sulfite using platinized cadmium sulfide powder  

Energy Technology Data Exchange (ETDEWEB)

Platinized cadmium sulfide powder suspended in a solution of sodium sulfite produces hydrogen efficiently by visible light. Sulfite ions are oxidized to sulfate and dithionate ions. 4 figures.

1983-09-29

18

Nitrogen nutrient status induces sexual differences in responses to cadmium in Populus yunnanensis  

UK PubMed Central (United Kingdom)

Populus yunnanensis was employed as a model species to detect sexual differences in growth, physiological, biochemical, and ultrastructural responses to cadmium (Cd) stress, nitrogen...Full Text Available

2011-10-01

19

Localization and Toxic Effects of Cadmium, Copper, and Uranium in Azolla1  

UK PubMed Central (United Kingdom)

The storage and distribution of copper, cadmium, and uranium and their effects on ionic contents in roots and shoots of Azolla filiculoides has been studied by x-ray microanalysis....Full Text Available

1988-09-01

20

Cadmium, Lead, and Other Metals in Relation to Semen Quality: Human Evidence for Molybdenum as a Male Reproductive Toxicant  

UK PubMed Central (United Kingdom)

BackgroundEvidence on human semen quality as it relates to exposure to various metals, both essential (e.g., zinc, copper) and nonessential (e.g., cadmium, lead), is inconsistent....Full Text Available

2008-11-01

21

Analysis of control methods: mercury and cadmium pollution.  

UK PubMed Central (United Kingdom)

Physical system conceptual models are developed to illustrate the various interconnecting pathways of metal flow. Economic use of mercury and cadmium, as representative toxic heavy metals, is inventoried,...Full Text Available

1975-12-01

22

Method of forming solar cells by grid contact isolation  

Energy Technology Data Exchange (ETDEWEB)

A solar cell structure is produced by a method comprising baking the solar cell, containing a gridded top layer of cuprous sulfide formed on a base of cadmium sulfide, for 20 minutes to 10 hours, to produce a copper doped cds electrically insulating region in the cadmium sulfide base near the interface of the cuprous sulfide and the cadmium sulfide; removing the cuprous sulfide, and the copper doped cds insulating region not covered by the grid, to provide a bare cadmium sulfide areas; and then forming a cuprous sulfide layer on the exposed areas not covered by the grid.

1982-03-16

23

Diffusion Zink Planting of Steels  

International Science & Technology Center (ISTC)

Research on Diffusion Zinc Cladding of Structural Steels, as Well as Their Mechanical and Corrosion Properties to Replace Their Cyanic Cadmium Plating

25

Tracing Cadmium from Culture to Spikelet: Noninvasive Imaging and Quantitative Characterization of Absorption, Transport, and Accumulation of Cadmium in an Intact Rice Plant1[W][OA]  

UK PubMed Central (United Kingdom)

We characterized the absorption and short-term translocation of cadmium (Cd) in rice (Oryza sativa ‘Nipponbare’) quantitatively using serial images observed with a positron-emitting...Full Text Available

2010-04-01

26

The recovery of zinc and cadmium following 6.1 MeV alpha particle irradiation at 4.2 K  

International Nuclear Information System (INIS)

The paper reports the recovery of zinc and cadmium following 6.1 MeV alpha particle irradiation at 4.2 K as studied by means of electrical reistivity measurements. Specimens of 10 #mu#m thick have been used in order to obtain a homogeneous defect distribution over the whole thickness of the specimen. The pre-irradiation resistivity ratios were 700 and 750 for cadmium and zinc, respectively. (Auth.).

27

Single-crystalline cadmium telluride anodic oxidation kinetics  

Science.gov (United States)

The authors have determined quantitative characteristics for oxide films forming on (111) surfaces of cadmium telluride single crystals on anodic oxidation in 0.1 M KOH: the constants in the Guenterschulze-Betz equation and the film growth constant, which is 2.4 nm/V, from which the activation energy for cadmium telluride electrooxidation has been calculated.

1988-10-10

28

Cadmium down-regulation of kidney Sp1 binding to mouse SGLT1 and SGLT2 gene promoters: Possible reaction of cadmium with the zinc finger domain of Sp1  

UK PubMed Central (United Kingdom)

Cadmium (Cd) exposure causes glucosuria (glucose in the urine). Previously, it was shown that Cd exposure of primary cultures of mouse kidney cells (PMKC) decreased mRNA levels of the glucose...Full Text Available

2010-05-01

29

In vivo effects of cadmium chloride on certain aspects of protein metabolism in tissues of a freshwater field crab Barytelphusa guerini  

Energy Technology Data Exchange (ETDEWEB)

Heavy metals discharged from industries are a major source of pollution which has become a threat to all forms of life. Among the various heavy metals, cadmium is known to be highly toxic even in low concentrations. The harmful effects of cadmium is attributed to its effects on sulfhydryl groups of enzymes, especially dehydrogenases. Various aspects of cadmium pollution on fishes have been extensively reviewed. A survey of the literature reveals that few attempts have been made to study the various aspects of cadmium toxicity in crustaceans and these studies were mainly devoted to marine forms. The freshwater crustaceans, particularly the freshwater field crab, Barytelphusa guerini, has received little attention. The present study reports the influence of cadmium on certain aspects of protein metabolism in the tissues of a freshwater field crab, Barytelphusa guerini, and important ...

1991-04-01

30

Assessment of cadmium in aquatic sediment using dialysis samplers with ion-exchange-resin collection  

Energy Technology Data Exchange (ETDEWEB)

Simultaneously extracted metals (SEM) and acid volatile sulfide (AVS) show the potential for toxicity on the basis of their ratio. Accordingly, the authors spiked cadmium in a range for which Cd/AVS ratios were from 0.2 to 10 in the sediment with its weight about 8 kg in each batch. Dialysis samplers with a cation ion-exchange resin (Dowex 50W-X4) collection were used in a laboratory for the determination of free cadmium concentrations in pore water of the collected sediment. When equilibrium was reached among cadmium in pore water, sediment, and ion-exchange resin, cadmium exchanged onto resin phase was regenerated with 1 N hydrochloric acid (OPTIMA grade) and determined using an atomic absorption spectrophotometer (Zeeman 5000) with a graphite furnace accessory. Cadmium determined using the dialysis sampler is considered as free cadmium which is related to the ...

1998-05-01

31

Protective role of selenium against renal toxicity induced by cadmium in rats  

International Nuclear Information System (INIS)

Cadmium is an environmental toxic metal implicated in human diseases. The mechanism of its toxicity is not fully understood. Therefore, the role of cadmium in renal toxicity, and the protective role of selenium against this toxicity were investigated. Forty-five male rats were used through out the study and divided into three groups of 15. The first group received saline solution daily for 10 days. The second group, received cadmium chloride (CdCl_2) (2 mg/kg body weight) intraperitoneally daily for a period of 10 days. The third group, received sodium selenite (1 mg/kg body weight, twice a day) and CdCl_2 (once a day) for a period of 10 days. The results showed that cadmium treatment increased renal lipid peroxidation (measured as malondialdehyde, MDA) which was associated with a significant decrease in the antioxidant systems such as reduced glutathione levels and the activities of glutathione ...

2007-06-25

32

In vivo effects of cadmium chloride on certain aspects of carbohydrate metabolism in the tissues of a freshwater field crab Barytelphusa guerini  

Energy Technology Data Exchange (ETDEWEB)

Cadmium is a toxic, non-essential heavy metal inhibiting numerous enzymes with functional sulfhydryl groups. Among the animals, aquatic organisms are most sensitive to heavy metals. Various aspects of toxic effects of cadmium pollution on fishes have been extensively reviewed. Survey of literature reveals that relatively few attempts have been made on the various aspects of cadmium toxicity in crustaceans and these studies were mainly devoted to marine forms. The freshwater crustaceans, particularly the freshwater field crab, Barytelphusa guerini, received less attention. This crab forms one of the major components of the paddy field ecosystem and has an edible importance among local populations. Apart from this, these crabs are easily available, maintainable in the laboratory and data obtained in this study can be extrapolated to other crustaceans. The present study reports the influence of cadmium on ...

1989-06-01

33

Health-hazard evaluation report HETA 85-354-1872, Asarco, Denver, Colorado  

Science.gov (United States)

An evaluation was made of possible hazardous working conditions at the ASARCO Globe facility, Denver, Colorado. The facility was involved in the recovery of cadmium from baghouse dust, a waste byproduct of nonferrous smelters. A medical study of kidney function was conducted in 45 current or former cadmium production workers; results were compared to those for 35 hospital workers. Kidney abnormalities were more common and more severe in the cadmium workers than in the hospital workers. Abnormalities of proximal tubular function included reduced reabsorption of beta-2-microglobulin, retinol binding protein, calcium and phosphate. Glomerular dysfunction was evidenced as elevated serum creatinine. As length of exposure to cadmium increased, changes became more apparent in workers. No reversal of the conditions was noted in workers who had ceased to be exposed to cadmium some time ...

1988-02-01

34

Plasmid-conferred tetracycline resistance confers collateral cadmium sensitivity to E. coli cells  

Energy Technology Data Exchange (ETDEWEB)

E. coli HB101 cells transformed to tetracycline resistance with the plasmids pMB9 or pBR322 display a 10/sup 5/-10/sup 6/-fold lower plating efficiency on agar containing 440 ..mu..M CdCl/sub 2/ than nontransformed cells. When DNA is inserted into the BamH1 site of the plasmid tet gene, or when DNA spanning the BamH1 site is deleted, tetracycline resistance and cadmium hypersensitivity are both lost. In contrast, insertion of DNA into the ampicillin resistance gene does not affect cadmium hypersensitivity.

1982-01-01

35

Cadmium and endrin toxicity to fish in waters containing mineral fibers  

Energy Technology Data Exchange (ETDEWEB)

Taconite tailings and their component asbestiform minerals in Lake Superior water had no demonstrable effect on the chronic toxicity of cadmium to the flagfish, Jordanella floridae. Maximum acceptable toxicant concentrations determined in life cycle tests, where effects on survival, growth, reproduction, and bioconcentration were used as endpoints, were between 3.3 to 7.4, 3.0 to 6.5, and 3.4 to 7.3 micrograms cadmium/liter at 0.004, 0.08, and 0.95 mg/liter taconite tailings concentrations, respectively.

1982-05-01

37

Optical and Structural Characteristics of Heavily Boron ...  

Science.gov (United States)

... Abstract : Cadmium telluride single crystals were subjected to multiple-energy boron ion implants with total doses up to 1.5 x 10 sq cm. ...

1988-05-24

39

Cadmium inhibits neurogenesis in zebrafish embryonic brain development  

International Nuclear Information System (INIS)

Cadmium is a non-essential heavy metal found abundantly in the environment. Children of women exposed to cadmium during pregnancy display lower motor and perceptual abilities. High cadmium body burden in children is also related to impaired intelligence and lowered school achievement. However, little is known about the molecular and cellular basis of developmental neurotoxicity in the sensitive early life stages of animals. In this study, we explore neurological deficits caused by cadmium during early embryonic stages in zebrafish by examining regionalization of the neural tube, pattern formation and cell fate determination, commitment of proneural genes and induction of neurogenesis. We show that cadmium-treated embryos developed a smaller head with unclear boundaries between the brain subdivisions, particularly in the mid-hindbrain region. Embryos display normal anterior to ...

2008-05-01

40

Separation and determination of cadmium and zinc as their thenoyltrifluoroacetone complexes with dibenzo-18-crown-6 by means of synergistic extraction and atomic absorption spectrometry  

Energy Technology Data Exchange (ETDEWEB)

A new method for the separation and determination of trace amounts of cadmium and zinc in water as their thenoyltrifluoroacetone (TTA) complexes with dibenzo-18-crown-6 (DB18C6) in o-dichlorobenzene has been established by means of synergistic extraction and back-extraction combined with atomic absorption spectrometry. The effect of various factors (synergism with TTA and DB18C6, shaking time, composition of the extracted species, and mutual separation etc.) on the extraction and back-extraction of cadmium and zinc has been in- vestigated. When the mixtures were extracted for 4 min at pH 4.9, only zinc was extracted quantitatively, whereas cadmium remained in the aqueous phase. After the phases were separated, cadmium was again extracted quantitatively at pH 7.5. Then, the two phases were each shaken with 0.05-0.1 mol/l HCl in order to back-extract cadmium and zinc from the organic ...

1997-01-01

41

Root-to-shoot Cd translocation via the xylem is the major process determining shoot and grain cadmium accumulation in rice  

UK PubMed Central (United Kingdom)

Physiological properties involved in divergent cadmium (Cd) accumulation among rice genotypes were characterized using the indica cultivar ‘Habataki’ (high Cd in grains)...Full Text Available

2009-07-01

42

Peculiarity of counterion - polyion interactions in aqueous solutions of copolymers of acrylamide with cadmium acrylate  

Energy Technology Data Exchange (ETDEWEB)

Binding of Cd/sup 2 +/ ions in aqueous solutions of statistical copolymers of acrylamide with cadmium acrylate with different content of ionogenic groups in copolymers was investigated by polarography, conductometry, viscometry and dialysis. It is shown that the degree of binding of Cd/sup 2 +/ ions increases with increasing of the content of ionogenic groups in the copolymer and with decreasing of ionic strength of the solution. The values of the degree of binding of Cd/sup 2 +/ ions obtained by polarography and dialysis show satisfactory agreement.

1984-02-01

43

A System-Based Comparison of Gene Expression Reveals Alterations in Oxidative Stress, Disruption of Ubiquitin-Proteasome System and Altered Cell Cycle Regulation after Exposure to Cadmium and Methylmercury in Mouse Embryonic Fibroblast  

UK PubMed Central (United Kingdom)

Environmental and occupational exposures to heavy metals such as methylmercury (MeHg) and cadmium (Cd) pose significant health risks to humans, including neurotoxicity. The underlying mechanisms of...Full Text Available

2010-04-01

44

Titanium Alloys for Medical Instrumentation  

International Science & Technology Center (ISTC)

The New Titanium Alloys With Increased Mechanical Properties and Corrosion Resistance for Medical Instruments and their Coatings

45

Molybdenum Alloys Optimal Structure  

International Science & Technology Center (ISTC)

Determination of Special Molybdenum Alloys Optimal Structure Using the Cybernetic Method

47

Corrosion Protection of special steels and alloys  

International Science & Technology Center (ISTC)

Development of the Corrosion Protection Technology for Special Steels and Alloys

48

Enrichment of trace cadmium by soybean protein for the analysis by atomic absorption method  

International Nuclear Information System (INIS)

A method for enrichment of the ppb level of cadmium in water by using the coagulation of soybean protein by adding acids or its complex-forming character with heavy metal ions was investigated. After adding fixed amounts of soybean milk and 2% sodium diethyldithiocarbamate(DDTC) aqueous solution and a suitable amount of delta-gluconic lactone (delta-GL) to a sample solution, the mixture was heated to boiling in order to coagulate the protein. The coagulum(soybean curd) was separated from the suspension by centrifugation and burned to ashes with a low temperature plasma asher. Then the cadmium enriched in it was determined by atomic absorption spectrometry. Various factors such as the pH of the sample solution, the amounts of soybean milk and the collection additives, and the concentration of NaCl in the sample solution on the recovery of cadmium were examined systematically. The best recovery was obtained under the ...

1975-01-01

49

Long-distance transport, vacuolar sequestration, tolerance, and transcriptional responses induced by cadmium and arsenic  

British Library Electronic Table of Contents (United Kingdom)

Iron, zinc, copper and manganese are essential metals for cellular enzyme functions while cadmium, mercury and the metalloid arsenic lack any biological function. Both, essential metals, at high concentrations, and non-essential metals and metalloids are extremely reactive and toxic. Therefore, plants have acquired specialized mechanisms to sense, transport and maintain essential metals within physiological concentrations and to detoxify non-essential metals and metalloids. This review focuses on the recent identification of transporters that sequester cadmium and arsenic in vacuoles and the mechanisms mediating the partitioning of these metal(loid)s between roots and shoots. We further discuss recent models of phloem-mediated long-distance transport, seed accumulation of Cd and As and rec...

2011-01-01

50

Lead, cadmium, chromium, cobalt, and copper in chicken feathers from Tuskegee, Alabama  

Energy Technology Data Exchange (ETDEWEB)

The feather has been widely used as a indicator tissue of metal exposure in birds. The feathers were collected from Tuskegee University poultry farm (TUPF) and Harrison Poultry farm (HPF) chicken and analyzed by Inductively Coupled Plasma Atomic Emission Spectroscopy for lead, cadmium, cobalt, chromium, and copper contaminations. The mean levels of lead, cadmium, cobalt, chromium, and copper in TUPF chicken were 3.67, 0.13, 12.23, 0.22, and 7.71 ppm, respectively, and in HPF chicken were 5.32, 0.096, 11.03, 0.15, and 8.06 ppm, respectively. The mean levels of these metals did not show any significant difference between TUPF and HPF chicken.

1994-12-31

51

Canadian soil quality criteria for lead, copper, arsenic, cadmium and mercury  

Energy Technology Data Exchange (ETDEWEB)

National soil quality criteria for the protection of ecological receptors, including livestock and wildlife, are currently under development in Canada. Based on an evaluation of direct soil contact and soil and food ingestion pathways for sensitive species, soil quality criteria for lead, copper, arsenic, cadmium and mercury for three land use categories have been derived. The draft values, in mg/kg soil, for agricultural, residential/parkland, commercial/industrial land uses are: mercury, 4, 4, 30; copper, 62, 62, 100; cadmium, 10, 10, 27; lead, 70, 250, 400; arsenic, 17, 17, 26. Critical data requirements in developing soil quality criteria are also reviewed.

1995-12-31

52

Thin Film Solar Cells and Solar Cell Testing, Volume II Proceedings of the Fourth Photovoltaic Specialists Conference  

Science.gov (United States)

Thin film solar cells and solar cell testing - photovoltaic cells, radiation damage to cadmium sulfide solar cells, and airplane testing of solar cells

1964-01-01

53

The role of metallothionein IIa in defending lens epithelial cells against cadmium and TBHP induced oxidative stress  

UK PubMed Central (United Kingdom)

PurposeHeavy metals and other forms of oxidative stress have been implicated as key factors in the formation of age-related cataract in humans. Metallothioneins are...Full Text Available

54

Phytochelatin Synthesis and Glutathione Levels in Response to Heavy Metals in Tomato Cells 1  

UK PubMed Central (United Kingdom)

Cell suspension cultures of tomato, Lycopersicon esculentum Mill. cv VFNT-Cherry, produce phytochelatins (poly[γ-glutamylcysteinyl]glycines) when exposed to cadmium. The synthesis...Full Text Available

1987-12-01

55

Partial Characterization of Cadmium-Binding Protein from Roots of Tomato 1  

UK PubMed Central (United Kingdom)

Cd-binding protein was extracted from tomato roots and purified on QAE-Sephadex A-25 and on Sephadex G-75 in 1 molar KCl buffer. The protein preparation was light brown and contained predominantly Cd...Full Text Available

1986-07-01

56

Optical and Structural Characteristics of Heavily Boron-Implanted CdTe.  

Science.gov (United States)

Cadmium telluride single crystals were subjected to multiple-energy boron ion implants with total doses up to 1.5 x 10 sq cm. Various diagnostic techniques were used to assess the structural and electronic properties of these crystals in their as-implante...

1988-01-01

57

NREL preprints for the 23rd IEEE Photovoltaic Specialists Conference  

Energy Technology Data Exchange (ETDEWEB)

Topics covered include various aspects of solar cell fabrication and performance. Aluminium-gallium arsenides, cadmium telluride, amorphous silicon, and copper-indium-gallium selenides are all characterized in their applicability in solar cells.

1993-05-01

58

Cadmium biosorption rate in protonated Sargassum biomass  

Energy Technology Data Exchange (ETDEWEB)

Biosorption of the heavy metal ion Cd{sup 2+} by protonated nonliving brown alga Sargassum fluitans biomass was accompanied by the release of hydrogen protons from the biomass. The uptake of cadmium and the release of proton matched each other throughout the biosorption process. The end-point titration methodology was used to maintain the constant pH 4.0 for developing the dynamic sorption rate. The sorption isotherm could be well represented by the Langmuir sorption model. A mass transfer model assuming the intraparticle diffusion in a one-dimensional thin plate as a controlling step was developed to describe the overall biosorption rate of cadmium ions in flat seaweed biomass particles. The overall biosorption mathematical model equations were solved numerically yielding the effective diffusion coefficient D{sub e} about 3.5 {times} 10{sup {minus}6} cm{sup 2}/s. This value matches that obtained for the desorption process and is approximately ...

1999-03-01

59

Assessment of battery technologies for electric vehicles  

Energy Technology Data Exchange (ETDEWEB)

This document, Part 2 of Volume 2, provides appendices to this report and includes the following technologies, zinc/air battery; lithium/molybdenum disulfide battery; sodium/sulfur battery; nickel/cadmium battery; nickel/iron battery; iron/oxygen battery and iron/air battery. (FI)

1990-02-01

60

Synthesis of histidine-stabilized cadmium sulfide quantum dots: Study of their fluorescence behaviour in the presence of adenine and guanine  

British Library Electronic Table of Contents (United Kingdom)

Cadmium sulfide particles have been synthesized in the aqueous medium using the amino acid histidine as a stabilizing agent. These particles demonstrate the phenomenon of size quantization effect. The fluorescence of histidine-stabilized CdS was found to be enhanced and quenched by the addition of DNA bases adenine and guanine, respectively. The fluorescence enhancement of CdS in the presence of adenine has been explained on the basis of interaction between the quantum dot stabilizer and the amino group of adenine. Quenching of CdS fluorescence by guanine occurs due to interaction of the substrate with the quantum dot surface.

2010-01-01

61

Biosorption process for removing heavy metal ions using water milfoil (Myriophyllum Spicatum) in contaminated water  

Energy Technology Data Exchange (ETDEWEB)

A small scale biomass metal contacting experiment was performed to screen the optimal plant species for biosorption and bioaccumulation of cadmium, zinc, nickel, lead, and copper. Experiments were also conducted to test the ability of the biomass to lower the metal concentrations below the US Environmental Protection Agency surface water discharge criteria. The minimum residual concentration was 0.1 mg/L for zinc, 0.004 mg/L for lead, and about 0.01 mg/L for cadmium, nickel, and lead. Results indicate that water milfoil can be used for bioremoval of metals.

1995-12-31

62

ASARCO to pay over $59 million for damages and cleanup costs at Denver smelting facility  

Science.gov (United States)

Since 1901, ASARCO, Inc. has owned and operated an 89-acre cadmium-refining smelter in the Globeville neighborhood of north Denver, Colorado. According to complaints filed by EPA and local residents, operations at the smelter have allegedly contaminated the air, ground water, surface water, and soil; contamination from arsenic, cadmium, lead, and zinc has occurred both onsite and offsite. EPA proposed to add the site to the National Priorities List (NPL) in May 1993.

1993-11-01

64

New Powder Technologies for Molybdenum Alloy Gun Barrel ...  

Science.gov (United States)

... MOLYBDENUM ALLOY GUN BARREL LINERS o0 in ... NEW POWDER TECHNOLOGIES FOR MOLYBDENUM ALLOY GUN BARREL LINERS ...

1985-06-01

67

Autocatalytic nucleation of omega phase in a beta-titanium alloy  

International Nuclear Information System (INIS)

Observations concerned with the formation of isothermal #omega# in the beta-titanium alloy RMI (38-6-44) are presented as part of a more general study of the aging characteristics of the alloy.

68

Distribution of blood lead, blood cadmium, urinary cadmium, and urinary arsenic levels in employees of a copper smelter  

Energy Technology Data Exchange (ETDEWEB)

A cross-sectional medical examination of a copper smelter work force included determination of blood lead (Pb-B), zinc protoporphyrin (ZPP), blood cadmium (Cd-B), urinary cadmium (Cd-U), and urinary arsenic (As-U), since it was known that such metal impurities were present in the copper concentrate. A total of 776 copper smelter employees (680 active and 96 retirees and ex-employees) were examined. Another 144 men, never employed in the smelter, but who had worked in copper mines (and sometimes in gold mines) were also examined. Mean Pb-B, ZPP, Cd-B, and As-U were significantly higher in active copper smelter employees than in retirees or miners, indicating exposure and absorption in the copper smelter. Significant correlations between Pb-B and Cd-B, and Cd-U and As-U were present, confirming the common source of absorption. Although there was evidence for an increased lead absorption, this was very moderate, with practically no Pb-B levels in ...

1984-02-01

69

Lead and cadmium in food. How do heavy metals find their way into our food and, how can the general public protect itself; Blei und Cadmium in Lebensmitteln; Wie kommen die Schwermetalle in unsere Nahrung? Und: Wie koennen sich Verbraucherinnen und Verbraucher schuetzen?  

Energy Technology Data Exchange (ETDEWEB)

The amounts of lead and cadmium produced and processed in these days are considerable. As a result, our environment is increasingly polluted by heavy metals and industrial installations, motor vehicles or incinerating plants appear to be among the main culprits here. Air and water are the media permitting the entry of heavy metals into our natural environment where they accumulate in the soil and then gradually migrate into the plants. Their further transport in the food constitutes the third step in the environmental spread of heavy metals. The consumption of muscle and organ meats, of vegetables, fruits, canned food and drinking water is unavoidably associated with some ingestion of lead and cadmium. The degree to which they are taken up and stored in different tissues is determined by absorption properties and the nutritional state of the organism. Cadmium tends to accumulate in the kidneys, lead is mainly stored in the ...

1992-08-01

70

The effects of alloying elements and dilution on the hot cracking sensitivity of welds in alloy 800  

International Nuclear Information System (INIS)

Results of hot cracking on welds with compositions between alloy 800 and AWS ER NiCr 3. Investigation of the influence of Si, Mn, Ti and Al on the hot cracking suscpetibility of the alloy 800. (orig.).

73

Metals and alloys : atmospheric corrosion testing : General requirements for field tests  

CERN Document Server

Metals and alloys : atmospheric corrosion testing : General requirements for field tests

1992-01-01

75

Effect of Yttrium on the Microstructure of Titanium Alloys,  

Science.gov (United States)

... Title : Effect of Yttrium on the Microstructure of Titanium Alloys,. ... The yttrium was added in the melting stage as an oxide or in the elemental form. ...

76

Ductile aluminide alloys for high temperature applications  

Energy Technology Data Exchange (ETDEWEB)

Alloys are described which contain nickel, aluminum, boron, iron and in some instances manganese, niobium and titanium.

1987-01-01

77

Corrosion and stress corrosion cracking of alloy 800 in water and steam at elevated temperatures  

International Nuclear Information System (INIS)

The importance that must be attached to the phenomenon of stress corrosion cracking of austenitic alloys is emphasized. The relation between chemical composition of various alloys and their sensitivity to cracking is shown with particular reference to the behaviour of Alloy 800. The different effects of alkaline anc chloride environments are discussed. Studies are reported of the general corrosion of Alloy 800 and other alloys in an environment representative of the primary coolant of PWR reactors; and of the behaviour of various alloys (including Alloy 800) in the conditions envisaged for their use for steam generators with superheat up to about 550 deg.C. (U.K.).

78

Corrosion mode diagrams for alloy 690 TT and alloy 800  

Energy Technology Data Exchange (ETDEWEB)

Due to the well-establish corrosion problems of Alloy 600 as a steam-generator material and the subsequent focus on thermally treated (TT) Alloy 690 and Alloy 800 as alternative materials, a systematic analysis of the corrosion behavior of these two latter alloys is warranted. Corrosion test results for Alloys 690 TT and 800 were collected and organized in the form of corrosion mode diagrams. Selected data for mill annealed (MA) Alloy 600 were also included for reference. The corrosion mode diagrams correlate the modes of corrosion degradation observed in tests as functions of the environment pH and electrochemical potential (ECP). The diagrams confirm that Alloys 690TT shows some susceptibility in caustic environments, and Alloy 800 shows susceptibility in both caustic and highly acidic environments. (authors). 6 figs., ...

1994-12-31

79

Corrosion mode diagrams for alloy 690 TT and alloy 800  

International Nuclear Information System (INIS)

Due to the well-establish corrosion problems of Alloy 600 as a steam-generator material and the subsequent focus on thermally treated (TT) Alloy 690 and Alloy 800 as alternative materials, a systematic analysis of the corrosion behavior of these two latter alloys is warranted. Corrosion test results for Alloys 690 TT and 800 were collected and organized in the form of corrosion mode diagrams. Selected data for mill annealed (MA) Alloy 600 were also included for reference. The corrosion mode diagrams correlate the modes of corrosion degradation observed in tests as functions of the environment pH and electrochemical potential (ECP). The diagrams confirm that Alloys 690TT shows some susceptibility in caustic environments, and Alloy 800 shows susceptibility in both caustic and highly acidic environments. (authors). 6 figs., ...

80

Extraction of copper-, nickel-, zinc- and cadmium complexes with 4-(2-pyridilazo)-resorcin and 2-aminopyridine  

International Nuclear Information System (INIS)

Extraction of copper-, nickel-, zinc- and cadmium complexes with 4-(2 pyridilazo)-resorcin (PAR) is studied in the presence of 2-aminopyridine (Am). Maximum optical densities of the extracts are attained at pH=7.5-8.0; 6.0-7.0; 6.5-7.0 and 7.0-8.0, respectively. The ratio of components in the complexes extractable by chloroform was defined by the method of isomolar series and equilibrium shift. It is established that nickel and copper are extracted to the organic phase as the NiAm(PAR)_2 and CuAmPAR complexes, and, in the case of zinc and cadmium, complexes of different composition are extracted, for example Zn(Am)_2PAR and ZnAm(PAR)_2. The light absorption spectra are studied and molar extinction coefficients of complex extracts are determined at lambdasub(max). It is shown that the general low of light absorption is observed within a sufficiently wide range of concentrations for all the elements.

1984-01-01

81

Enhanced cadmium cytotoxicity in A549 cells with reduced glutathione levels is due to neither enhanced cadmium accumulation nor reduced metallothionein synthesis  

International Nuclear Information System (INIS)

Glutathione (GSH) depletion sensitizes human lung carcinoma (A549-T27) cells to the cytotoxic effects of Cd++. The effects of GSH depletion on Cd++ accumulation and Cd++-induced metallothionein (MT) content were investigated to determine the possible role of these Cd++ responses in the sensitization process. Cellular GSH was depleted to 20% to 25% of control levels with buthionine sulfoximine (BSO), or diethyl maleate (DEM), respectively. Neither treatment significantly affected Cd++-induced accumulation of exogenous 35s-cysteine into intracellular MT in a dose-dependent fashion. The results indicate that neither enhanced Cd++ accumulation nor reduced MT synthesis plays a primary role in affecting enhanced Cd++ cytotoxicity in A549 cells with reduced GSH levels. Although BSO inhibition of GSH synthesis enhanced MT synthesis, it sensitized the cells to Cd++, which suggests an additive effect of GSH and MT in cadmium cytoprotection. This observation also raises the ...

82

Enhanced biosorptive removal of cadmium from aqueous solutions by silicon dioxide nano-powder, heat inactivated and immobilized Aspergillus ustus  

British Library Electronic Table of Contents (United Kingdom)

Heat inactivated Aspergillus ustus (Asp), silicon dioxide-nano-powder (N Si), and silicon dioxide nano-powder-combined-heat inactivated Aspergillus ustus (N Si Asp) were used to study the biosorption of Cd(II) from aqueous solutions via batch equilibrium technique. Surface characterization and immobilization of the fungal cells on silicon dioxide-nano-powder were examined and confirmed by using FT-IR and ESM analysis. Cadmium biosorption processes were investigated under the effect of pH, contact time, sorbent dosage and initial metal concentration. The three examined sorbents were found to exhibit maximum mmolg^-^1 capacity values in pH 7.0. The maximum determined cadmium capacity by silicon dioxide-nano-powder (N Si) (600mmolg^-^1) was found higher than that exhibited by the heat inactiv...

2011-01-01

83

A comparison of the low cycle fatigue behavior of alloy 800 and alloy 800H  

International Nuclear Information System (INIS)

The low cycle fatigue testing was carried out to provide a basis for comparison of the behavior of the two kinds of Alloy 800 (low carbon Alloy 800 and high carbon Alloy 800H). The testing was done at temperatures of 500"0C and 650"0C either with or without hold. The results obtained were as follows: (1) At 650"0C, the low-cycle fatigue life was essentially the same for the two alloys on the basis of strain amplitude, but Alloy 800H had a longer life on the basis of stress amplitude. (2) At 500"0C, the two alloys exhibited longer lives than at 650"0C, with Alloy 800 exhibiting 2-3 times longer life than Alloy 800H when compared on the basis of plastic strain range. At this temperature the stress range showed the maximum for Alloy 800H. (3) When a creep effect was introduced either by way of a hold ...

1979-06-01

84

Production of titanium alloys with uniform distribution of heat resisting metals  

International Nuclear Information System (INIS)

Consideration is given to the process of the formation of a titanium sponge alloyed with niobium or tantalum, in the joint metallic reduction of titanium, niobium and tantanum chlorides. A percentage composition of the phases observed and the structure of the alloyed sponge have been studied. It is shown that after one remelting operation of the alloyed sponge the alloys of titanium with niobium and tantalum have a uniform component distribution. At the stage of chloride reduction there appear solid solutions based on titanium and an alloying component. The stage of vacuum separation of the reaction mass is associated with a mutual dissolution of the primary phases and the formation of the solid solutions of the alloyed titanium sponge, which, by their composition, are close to the desired alloy composition. The principal features of the ...

85

Trace analysis in cadmium telluride by heavy ion induced X-ray emission and by SIMS  

International Nuclear Information System (INIS)

The possibilities of using both selective heavy ion induced X-ray emission and secondary ion mass spectroscopy (SIMS), for the identification of impurities present at low concentrations in cadmium telluride are examined. The relative concentrations of the impurities along CdTe crystals have been determined by exciting the X-ray emission of the elements in several slices with Ar and Kr ions and by comparing the relative characteristic X-ray emission yields. As a consequence of the quasimolecular inner shell ionization mechanism in heavy ion-atom collisions, Ar and Kr ions allow a strong excitation of the main impurities seen by SIMS namely Si, Cl and Ge, As, with only a minor contribution of Cd and Te. From the changes of the concentrations of the various impurities along the crystal, informations about segregation coefficients and compensation can be obtained.

2007-02-01

86

The Effect of Contacts on the Counting Characteristics of Heavily Doped Normal-Type Cadmium-Telluride  

Science.gov (United States)

Cadmium telluride single crystals were grown heavily doped with chloride by the THM method. The resulting crystals were n-type with free carrier concentrations of the order of 10('12)/cm at room temperature. Hall effect studies revealed room temperature mobilities between 30 and 350 cm('2)/v-sec and resistivites between 2 x 10('3) and 10('4) ohm-cm. Studies were made of the gamma and alpha counting characteristics of these crystals with metal, metal-semiconductor, and metal-insulator electrodes. It was found that the MIS and MSS structures resulted in significant improvement over the MS structures in counting, signal-to-noise and energy resolution.

1985-01-01

87

Studies on biosorption and toxicity of heavy metals in bacteria; Untersuchungen zur Biosorption und zur Toxizitaet von Schwermetallen auf Bakterien  

Energy Technology Data Exchange (ETDEWEB)

Biosorption behaviour of and toxic effects of heavy metals in submersed and immobilised microorganisms was studied in batches and in continuous processes in an airlift-recycle reactor. Nickel, cadmium, and zinc were used as heavy metals. (orig./VHE) [Deutsch] Am Beispiel einer Naphthalin-2-sulfonsaeure-abbauenden Kultur wurde das Biosorptionsverhalten und die toxische Wirkung von Schwermetallen auf submerse und immobilisierte Mikroorganismen im Batch-Ansatz und im kontinuierlichen Betrieb in einem Airlift-Schlaufenreaktor untersucht. Als Schwermetalle wurden Nickel, Cadmium und Zink eingesetzt. (orig./VHE)

1993-09-01

88

Roles of biomarkers in evaluating interactions among mixtures of lead, cadmium and arsenic  

British Library Electronic Table of Contents (United Kingdom)

Human exposure to environmental chemicals is most correctly characterized as exposure to mixtures of these agents. The metals/metalloids, lead (Pb), cadmium (Cd), and arsenic (As), are among the leading toxic agents detected in the environment. Exposure to these elements, particularly at chronic low dose levels, is still a major public health concern. Concurrent exposure to Pb, Cd, or As may produce additive or synergistic interactions or even new effects that are not seen in single component exposures. Evaluating these interactions on a mechanistic basis is essential for risk assessment and management of metal/metalloid mixtures. This paper will review a number of individual studies that addressed interactions of these metals/metalloids in both experimental and human exposure studies with...

2008-01-01

89

Fertilizer amendment for improving the phytoextraction of cadmium by a hyperaccumulator Rorippa globosa (Turcz.) Thell  

British Library Electronic Table of Contents (United Kingdom)

Purpose Two main pathways of phytoremediation of heavy metal-contaminated soils are phytostabilization and phytoextraction. Some soil amendments can strengthen phytostabilization or phytoextraction through either reducing heavy metal bioavailability in soil or increasing the heavy metal accumulation capacity of the hyperaccumulator (enhancing heavy metal concentration or shoot biomass of the hyperaccumulator). Urea and chicken manure are often used as fertilizers. This research will explore their effects on a newly found hyperaccumulator, Rorippa globosa (Turcz.) Thell., phytoremediating cadmium (Cd). Materials and methods Pot culture experiment was conducted to study the accumulation characteristics of R. globosa at different Cd contamination concentrations under one fertilizer level (1?g...

2011-01-01

90

Development of engineering technology basis for pyrometallurgical reprocessing: development of transport technology and pyro-process equipments  

International Nuclear Information System (INIS)

Development of the engineering technology basis of pyrometallurgical reprocessing is a key issue for industrialization. For development of the transport technologies of molten salt and liquid cadmium at around 773 K, a salt transport test rig and a metal transport test rig were newly installed in an Ar glove box. Function of the salt transport test rig was confirmed with LiCl-KCl molten salt, and the transport behaviour of molten salt was found to follow that of water. The molten salt/liquid metal contactor for Ln/An separation was newly designed and installed. The test with a single-stage contactor was successful with simulated elements, and a three-stage contactor is now under development. A large-scale electro-refiner with a function to transport molten salt and liquid cadmium were newly designed, and to be installed for demonstration test with simulated materials. (authors)

2006-09-25

91

Determination of some minor and trace elements in iron ores by ion exchange chromatography, spectrophotometry and atomic absorption spectrometry  

International Nuclear Information System (INIS)

A method is described for determination of aluminium, cadmium, cobalt, chromium, copper, calcium, magnesium, sodium, potassium, manganese, nickel, lead, strontium, zinc, titanium and vanadium in iron ore. After dissolution, a 1 gram sample of iron ore is applied to a column of AGI-X8 anion exchange resin (chloride form), in 100 ml of 7M HCl. Aluminium, chromium, calcium, magnesium, sodium, potassium, manganese, nickel, lead, strontium, titanium and vanadium are eluted with 7M HCl; iron, copper and cobalt are eluted with 0.5M HCl; cadmium and zinc are eluted with 2M HNO_3. Iron is subsequently removed from copper and cobalt by a solvent extraction with methyl isobutyl ketone. The elements are determined in the eluates by atomic absorption spectrometry, except for titanium and vanadium, which are determined spectrophotometrically.

92

Biosorption of heavy metals on fungal biomass  

Energy Technology Data Exchange (ETDEWEB)

A method of using fungi in removing heavy metal from wastewater was discussed. Fungi for this purpose can be obtained inexpensively, and on a constant basis from industrial fermentation processes. The biosorption of lead, cadmium and nickel on fungal stock cultures, was investigated. In these experiments, the fungal stock used was Aspergillus niger and Rhizopus stolonfier. Alkali pre-treatment of the fungal biomass improved the metal biosorptive capacity in comparison to live cells. The effect of alkali treatment, however, varied,showing highest biosorptive capacity for lead and least for nickel. Results showed that metal biosorption of metallic ions increased with an increase in pH from 3.2 to 4.0. Equilibrium times of five hours were observed for the biosorption of lead and cadmium, while the equilibrium time for nickel was three hours. 10 refs., 3 tabs., 7 figs.

1996-09-01

93

A 1500-year record of lead, copper, arsenic, cadmium, zinc level in Antarctic seal hairs and sediments  

British Library Electronic Table of Contents (United Kingdom)

To reconstruct the profiles of heavy metal levels in the South Ocean ecosystem of Antarctica, the concentrations of lead (Pb), copper (Cu), arsenic (As), cadmium (Cd), and zinc (Zn) in seal hairs and lake sediments spanning the past 1500?years from Fildes Peninsula of King George Island and in weathering lake sediments from Nelson Island of West Antarctica were determined. The lead contents in the seal hairs and the weathering sediments show a sharp increase since the late 1800s, very likely due to anthropogenic contamination from modern industries. After the 1980s, the Pb content in seal hairs dropped by one-third, apparently due to the reduced usage of leaded gasoline in the Southern Hemisphere. Copper arises mainly from the weathering process, and its level may be substantially affected...

2006-01-01

94

Tensile strength of eutectic, directionally solidified alloys based on the Co-Cr-C-system  

International Nuclear Information System (INIS)

The influence of various alloy elements on tensile strength of the eutectic, directionally solidified superalloy 73 C was determined. The tensile properties of the base alloy has been increased by Al, Y and C as alloying elements, while Ni and Ti showed a decreasing effect (alloy softening). However, ductility and thermo-fatigue behaviour had been influenced in a positive way by these elements. The specific meachanism caused by the different elements are discussed. (orig.).

1981-01-01

95

Quartz ceramics alloying  

International Nuclear Information System (INIS)

The following methods of quartz ceramics alloying were considered: alloying of initial quartz glass; introduction of alloying additive into water slip of quartz glass; porous materials impregnation with salt aqueous solutions and subsequent salt thermal decomposition with formation of stable oxides in pores of ceramics. Oxygen free compounds BN, SiB_4, SiC, Si_3N_4, REM oxides and transition metal oxides were used as alloying additives. Main properties of the materials and compositions obtained are presented.

96

Processing and properties of Nb-Ti-base alloys  

Energy Technology Data Exchange (ETDEWEB)

The processing characteristics, tensile properties, and oxidation response of two Nb-Ti-Al-Cr alloys were investigated. One creep test at 650 C and 172 MPa was conducted on the base alloy, which contained 40Nb-40Ti-10Al-10Cr. A second alloy was modified with 0.11 at.% C and 0.07 at.% Y. Alloys were arc melted in a chamber backfilled with argon, drop cast into a water-cooled copper mold, and cold rolled to obtain a 0.8-mm sheet. The sheet was annealed at 1,100 C for 0.5 h. Longitudinal tensile specimens and oxidation specimens were obtained for both the base alloy and the modified alloy. Tensile properties were obtained for the base alloy at room temperature, 400, 600, 700, 800, 900, and 1,000 C and for the modified alloy at room temperature, 400, 600, 700, and 800 C. Oxidation tests the base alloy ...

1993-08-01

97

Processing and properties of Nb-Ti based alloys  

Energy Technology Data Exchange (ETDEWEB)

The processing characteristics, tensile properties, and oxidation response of two Nb-Ti-Al-Cr alloys were investigated. One creep tests at 650{degrees}C and 172 MPa was conducted on the base alloy which contained 40Nb-40-Ti-10Al-10Cr. A second alloy was modified with 0.11 at. % carbon and 0.07 at. % yttrium. Alloys were arc melted in a chamber backfilled with argon, drop cast into a water-cooled copper mold, and cold rolled to obtain a 0.8-mm sheet. The sheet was annealed at 1100{degrees}C for 0.5 h. Longitudinal tensile specimens and oxidation specimens were obtained for both the base alloy and the modified alloy. Tensile properties were obtained for the base alloy at room temperature, 400, 600, 700, 800, 900, and 1000{degrees}C, and for the modified alloy at room temperature, 400, 600, 700, and 800{degrees}C. Oxidation ...

1992-01-01

98

Nickel alloy clad steel plate for flue gas desulfurization applications  

Energy Technology Data Exchange (ETDEWEB)

The use of nickel alloys in Flue Gas Desulfurization (FGD) applications is described. Recently, nickel alloys 625 and C-276 have been clad to carbon steel plate. Production and properties of the clad plate are reviewed and a brief discussion is presented on production, fabrication and welding. Laboratory and field corrosion tests in SO/sub 2/ scrubber environments suggest that alloy 625 and C-276 clad steel plates are as corrosion resistant as the solid alloy plate.

1987-01-01

99

Investigation into superplasticity of Be alloys  

International Nuclear Information System (INIS)

Investigated are the characteristics of high-temperature plastic deformation the velocity sensitivity of flow stresses, deformation curves, flow stresses, deformation before rupture - as well as the structure of beryllium alloys containing nickel (0.5-4 %), yttrium (0.5-2 %) and aluminium (38 %). The alloys containing nickel (2%) and yttrium (0.5 %) are superplastic, however, deformation before fracture of the alloys is lower than that of the unalloyed beryllium. The singularities of high-temperature plastic flow of the alloys and the causes of deterioration of their plasticity are determined.

100

Hydrogen effect or texture and deformation mechanism in #beta#-titanium alloy cold rolling  

International Nuclear Information System (INIS)

The relationships of hydrogen alloyed #beta#-titanium alloy deformation behaviour to its microstructure and texture are investigated. It is shown that plasticity increases and strain induced texture changes at low hydrogen contents (0.1-0.2 mass %). Possible mechanisms responsible for specific features of #beta#-Ti alloy deformation are discussed. The study is made using alloy VT35 doped with hydrogen

1999-09-01

101

Comparative behavior of Alloys 600, 690 and 800 in caustic environments  

Energy Technology Data Exchange (ETDEWEB)

Since 1991, secondary side cracking has become a major concern in EDF steam generators. At 350 C, IGSCC of Alloy 600 was found in pure NaOH solutions from 4 to 500 g/l, with a maximum at 100 g/l. From the present results and available data, IGSCC of Alloy 690 occurred in pure NaOH solutions from 40 to 500 g/l, but the greatest sensitivity was observed at 100 g/l. TG/IGSCC of Alloy 800 became more severe with increasing NaOH solutions, from 10 to 500 g/l. On the whole, the ranking for SCC-resistance was Alloy 600 < Alloy 800 < Alloy 690. A significant improvement was still obtained with 690TT with intergranular carbides (industrial tubes) and perhaps with Alloy 800 NG (nuclear grade), but both alloys cracked at the highest stresses. IGSCC susceptibility of Alloy 600 MA was higher for the tubes ...

1995-12-31

102

Production of intergranular attack of alloy 600, alloy 690, and alloy 800 tubing in tubesheet crevices: Topical report  

Energy Technology Data Exchange (ETDEWEB)

Three model boilers, manufactured to simulate full-size tube sheet crevices, were tested with various secondary side environments. The first was faulted with organics representative of the decomposition of humic acid. The second was faulted with sodium carbonate and sodium hydroxide, while the third was faulted with sodium sulfate and sodium hydroxide. Each model contained seven tubes, which included Alloy 600 in the mill-annealed (MA) and thermally-treated (TT) conditions and Alloy 690 in the thermally-treated condition. Two models contained Alloy 800 tubes in the mill-annealed condition and one had Alloy 800 in the mill-annealed/cold-worked/glass-bead-peened condition. Two different sizes of tubesheet crevices were used in all model boilers. In the organics-faulted boiler, tubes of Alloy 600MA, Alloy 690TT and Alloy 800MA experienced no ...

1987-07-01

103

Production of intergranular attack of alloy 600, alloy 690, and alloy 800 tubing in tubesheet crevices: Topical report  

International Nuclear Information System (INIS)

Three model boilers, manufactured to simulate full-size tube sheet crevices, were tested with various secondary side environments. The first was faulted with organics representative of the decomposition of humic acid. The second was faulted with sodium carbonate and sodium hydroxide, while the third was faulted with sodium sulfate and sodium hydroxide. Each model contained seven tubes, which included Alloy 600 in the mill-annealed (MA) and thermally-treated (TT) conditions and Alloy 690 in the thermally-treated condition. Two models contained Alloy 800 tubes in the mill-annealed condition and one had Alloy 800 in the mill-annealed/cold-worked/glass-bead-peened condition. Two different sizes of tubesheet crevices were used in all model boilers. In the organics-faulted boiler, tubes of Alloy 600MA, Alloy 690TT and Alloy 800MA experienced no ...

104

Laser hardening of titanium-zirconium alloy  

International Nuclear Information System (INIS)

The methods of surface modification of Ti-Zr alloy by laser treatment are considered. Characteristics of laser modification without- and with surface melting and with melting in different gaseous environments and with nickel microalloying are presented. Maximum depth, hardness and corrosion resistance are observed under nickel laser alloying.

105

Development of Mg alloy sheets via strip casting  

Energy Technology Data Exchange (ETDEWEB)

AZ31 and experimental ZMA611 alloys were strip cast into 2 mm thick strips. The as-cast AZ31 alloy strip consists of columnar dendrites. On the other hand, as-cast ZMA611 alloy strip shows equiaxed dendritic structure through the thickness of strip. These alloys were subjected to various thermomechanical treatments and their tensile properties were evaluated. Strip cast AZ31 alloy in H24 condition has equivalent yield and tensile strengths with similar ductility compared to commercial ingot cast AZ31-H24 alloy, indicating that strip casting is a viable process for the fabrication of Mg alloy strips. The ZMA611 alloy has a large volume fraction of fine dispersoid particles in the microstructure, resulting from the beneficial effect of strip casting on microstructural refinement. It has been shown that the ZMA611 ...

2005-07-01

106

Wear resistance of a laser surface alloyed Ti-6Al-4V alloy  

Energy Technology Data Exchange (ETDEWEB)

Laser surface alloying with gaseous nitrogen was utilized to improve the wear resistance of a Ti-6Al-4V alloy. Wear-resistant composite coatings reinforced by hard TiN dendrites were produced 'in-situ' on a substrate of a Ti-6Al-4V alloy. The hardness and wear resistance of the laser alloyed coating under two-body abrasive and block-on-ring full-sliding wear conditions were significantly enhanced. (orig.)

2000-08-01

107

Development of ALLOY 800 for PWR/SG tubings resistant to IGSCC and general corrosion  

Energy Technology Data Exchange (ETDEWEB)

Resistance of ALLOY 800 as a PWR/SG tubings to IGC/IGSCC and Ni, Co release into high temperature water was evaluated as compared with ALLOYs 600 and 690. The study to improve the resistance to IGSCC and general corrosion was also made. From the results, ALLOY 800 was evaluated to be the most reliable among the high Ni alloys tested. In addition, the alloy would obtain further reliability in IGSCC and general corrosion resistance by the combined addition of Ti and Nb, and the prior oxidation treatments, respectively. (author).

1989-07-01

108

Corrosion resistance of #gamma#-solid solution and hardening #gamma#'-phase of nickel alloys in sodium sulfate and chloride melts  

International Nuclear Information System (INIS)

Corrosion testings of model alloys, corresponding by chemical composition to simple and complex-alloyed #gamma#- and #gamma#'-phases of nickel heat-resistant alloys are conducted in sodium sulfate and chloride melts. It is ascertained that heat resistant nickel alloys containing over 50 % of hardening #gamma#'-phase, are subject to disastrous sulfide corrosion (SC). Resistance against SC alloys containing below 50 % of #gamma#'-phase is determined by the resistance of #gamma#-solid solution. 10 refs., 3 figs., 2 tabs.

109

Ultra High Strength Beta Titanium Alloy for Fasteners.  

Science.gov (United States)

... Accession Number : ADD151811. Title : Ultra High Strength Beta Titanium Alloy for Fasteners. Descriptive Note : Journal article,. ...

110

Thermophysical Properties of Matter - The TPRC Data Series. ...  

Science.gov (United States)

... alloys--Lanthanum-- Magnesium--Magnasium &11oy8--Hagn*31Uft compounds--Manxganese--Manganes. alloys-- Mercury ...

2011-05-14

111

THERMAL STABILITY OF ALPHA-BETA TITANIUM ALLOY Ti ...  

Science.gov (United States)

... Accession Number : ADD109273. Title : THERMAL STABILITY OF ALPHA-BETA TITANIUM ALLOY Ti-5Al-2Cr-1Fe,. Corporate Author : ...

1975-08-01

112

THE SUSCEPTAEILITY OF MATERIALS  

Science.gov (United States)

Hilled Bend Spechene of an Alpha-Beta Titanium Alloy. Ti-6M14V. ..... The all beta titanium alloy was nllled from both sides; only the edges were taped. ...

113

Structure and Mechanical Properties of Boron-Doped Cubic ...  

Science.gov (United States)

... by the boron doping in most of the alloys except for Al66Mn9Zr25 + 50 ppm B alloy; permanent deformation at ultimate compressive strength is not ...

114

SIMS imaging studies of the corrosion of alloy 800 and alloy 600 surfaces under secondary side boiler conditions  

Energy Technology Data Exchange (ETDEWEB)

The nickel-rich superalloys Alloy 600 and Alloy 800 have been corroded in mildly alkaline deuterated aqueous conditions typical of secondary coolant circuits in a nuclear power station. The oxide films and substrates of these alloys have been analysed by imaging SIMS depth profiling, which makes it possible to describe elemental distribution in all three dimensions. The measurement of the distribution of the secondary ions NiO[sup -], FeO[sup -] and CrO[sup -] appears useful for detailing the behaviour of nickel, iron and chromium within oxidized phases. The measurement of D[sup -] distribution outlines the extent of oxide hydration. For Alloy 800, evidence of sodium migration into the grain boundaries of the alloy substrate is found. For Alloy 600, no grain boundary sodium ingress can be identified under comparable corrosion conditions. (author).

1992-08-01

115

SIMS imaging studies of the corrosion of alloy 800 and alloy 600 surfaces under secondary side boiler conditions  

International Nuclear Information System (INIS)

The nickel-rich superalloys Alloy 600 and Alloy 800 have been corroded in mildly alkaline deuterated aqueous conditions typical of secondary coolant circuits in a nuclear power station. The oxide films and substrates of these alloys have been analysed by imaging SIMS depth profiling, which makes it possible to describe elemental distribution in all three dimensions. The measurement of the distribution of the secondary ions NiO"-, FeO"- and CrO"- appears useful for detailing the behaviour of nickel, iron and chromium within oxidized phases. The measurement of D"- distribution outlines the extent of oxide hydration. For Alloy 800, evidence of sodium migration into the grain boundaries of the alloy substrate is found. For Alloy 600, no grain boundary sodium ingress can be identified under comparable corrosion conditions. (author).

117

Reduced activation activities  

Energy Technology Data Exchange (ETDEWEB)

Four low activation alloy classes, two austenitic and two ferritic, have been incorporated into the MOTA-1B experiment in the FFTF reactor to provide an early assessment of the suitability of such alloys for reactor service.

1984-01-01

118

Metal dusting behaviour of welded Ni-base alloys with different surface finish  

Energy Technology Data Exchange (ETDEWEB)

Welded Ni-base alloys and Alloy 800 were exposed under metal dusting conditions at 600 C and 650 C for up to 6000 hours. Alloy 800 was attacked very strongly already in the first days and Alloy 600 also rather soon and widespread, on both materials attack started mainly in the heat affected zone. Several surface states of Alloy 600: brushed, ground, sand-blasted and pickled were tried only grinding caused a modest delay and decrease of metal dusting attack. Generally the attack was less widespread but deeper at 650 C than at 600 C, also for Alloy 601 and 602. The latter alloys show minor, mainly local attack, but especially the welds are affected. TIG welding led to better resistance than hand-welding. (Abstract Copyright [2003], Wiley Periodicals, Inc.)

2003-10-01

119

Hydrogen in titanium alloy with 16 at% Mo  

International Nuclear Information System (INIS)

The effect of various hydrogen concentrations on the crystal lattice period and the hardness of titanium alloy was examined, the alloy containing about 16 at.% Mo (27.5 wt. % Mo) and having #beta# structure. The peculiar features of the mechanism of plastic deformation of the alloy were studied after adding hydrogen to it. A dependence of the crystal lattice period on the concentration of hydrogen was obtained for TixMoxH_2 alloy. It has been established that the hardness of the Ti-Mo alloy does not change when hydrogen is added to it. The presence of hydrogen introduces changes into the mechanism of deformation of #beta#-titanium alloy. The configuration of the inverse pole figures after rolling proves that the transverse slip process in an alloy with hydrogen is hampered, and that the coplanar slip process is developing in it.

120

Environmental Cracking of the Alpha-Beta Titanium Alloy, Ti ...  

Science.gov (United States)

... Accession Number : ADD120492. Title : Environmental Cracking of the Alpha-Beta Titanium Alloy, Ti-6Al-6V-2Sn,. Corporate ...

121

Effect of Stress and Strain Path on Cavity Closure During Hot ...  

Science.gov (United States)

... CLOSURE DURING HOT WORKING OF AN ALPHA/BETA TITANIUM ALLOY (PREPRINT) ... HOT WORKING OF AN ALPHA/BETA TITANIUM ALLOY ...

2007-07-01

122

Differences in synchrotron radiation induced gas desorption from stainless steel and aluminium alloy  

CERN Document Server

Differences in synchrotron radiation induced gas desorption from stainless steel and aluminium alloy

1990-01-01

123

Development of a FeCoNb Alloy to be used in Eddy Current ...  

Science.gov (United States)

... Accession Number : ADD336001. Title : Development of a FeCoNb Alloy to be used in Eddy Current Probes for Testing Ferromagnetic Tubes,. ...

124

Development of Lead-Free Copper Alloy-Graphite Castings  

Energy Technology Data Exchange (ETDEWEB)

In this project, graphite is used as a substitute for lead in order to maintain the machinability of plumbing components at the level of leaded brass. Graphite dispersed in Cu alloy was observed to impart good machinability and reduce the sizes of chips during machining of plumbing components in a manner similar to lead. Copper alloys containing dispersed graphite particles could be successfully cast in several plumbing fixtures which exhibited acceptable corrosion rate, solderability, platability, and pressure tightness. The power consumption for machining of composites was also lower than that of the matrix alloy. In addition, centrifugally cast copper alloy cylinders containing graphite particles were successfully made. These cylinders can therefore be used for bearing applications, as substitutes for lead-containing copper alloys. The results indicate that copper graphite ...

1999-10-01

125

DUCTILITY RATIO OF AGED BETA TITANIUM ALLOY  

Science.gov (United States)

... Title : DUCTILITY RATIO OF AGED BETA TITANIUM ALLOY. Corporate Author : NEW YORK UNIV NY SCHOOL OF ENGINEERING AND SCIENCE. ...

1962-01-02

126

Beta-21S: A High Temperature Metastable Beta Titanium Alloy ...  

Science.gov (United States)

... Accession Number : ADD144314. Title : Beta-21S: A High Temperature Metastable Beta Titanium Alloy. Descriptive Note : Conference Proceedings, ...

127

An overview of beta titanium alloy environmental behavior  

International Nuclear Information System (INIS)

Stemming from their unique combination of elevated strength, low density, and good overall corrosion resistance, beta titanium alloys have become attractive candidate materials for critical, high-stress, components in corrosive services. An overview of the comparative corrosion resistance of beta alloys to conventional alpha and alpha/beta titanium alloys in common industrial and aerospace service environments generally reveals attractive behavior depending on the environment and alloy composition and, in some cases, alloy condition. Expanded performance windows are especially noted for the molybdenum-rich beta alloys, particularly in regard to resisting reducing acids, stress corrosion, and high temperature localized chloride attack, along with hydrogen and oxidation resistance. Where applicable, implications of this enhanced corrosion performance on current ...

1993-02-21

128

The separation and determination of trace elements in iron ore  

International Nuclear Information System (INIS)

The separation, concentration, and determination of trace elements in iron ores are described. After the sample has been dissolved, the iron is separated by liquid-liquid extraction with a liquid cation-exchanger, di-(2-ethylhexyl) phosphoric acid. The trace elements aluminium, cadmium, calcium, chromium, cobalt, copper, lead, magnesium, manganese, mercury, potassium, sodium, vanadium, and zinc are determined in the aqueous phase by atomic-absorption spectrophotometry.

2008-05-01

129

Indium-cadmium-oxide films having exceptional electrical conductivity and optical transparency: Clues for optimizing transparent conductors  

UK PubMed Central (United Kingdom)

Materials with high electrical conductivity and optical transparency are needed for future flat panel display, solar energy, and other opto-electronic technologies. InxCd1-xO...Full Text Available

2001-06-19

130

Identification of Thlaspi caerulescens Genes That May Be Involved in Heavy Metal Hyperaccumulation and Tolerance. Characterization of a Novel Heavy Metal Transporting ATPase1  

UK PubMed Central (United Kingdom)

Thlaspi caerulescens is a heavy metal hyperaccumulator plant species that is able to accumulate extremely high levels of zinc (Zn) and cadmium (Cd) in its shoots (30,000 μg...Full Text Available

2004-11-01

131

Heavy Metals in selected Edible Vegetables and their daily intake in Sanandaj, Iran  

Energy Technology Data Exchange (ETDEWEB)

The levels of four different heavy metals [cadmium (Cd), lead (Pb), chromium (Cr) and copper (Cu)] were determined in various vegetables [leek (Allium ampeloprasum), sweet basil (Ocimum basilicum), parsley (Petroselium cripsum), gardem cress (lepidium sativum) and tarragon (Artemisia dracuncullus)] cultivated around the Sanandaj city. (Author)

2009-07-01

132

Heavy Metals in selected Edible Vegetables and their daily intake in Sanandaj, Iran  

International Nuclear Information System (INIS)

The levels of four different heavy metals [cadmium (Cd), lead (Pb), chromium (Cr) and copper (Cu)] were determined in various vegetables [leek (Allium ampeloprasum), sweet basil (Ocimum basilicum), parsley (Petroselium cripsum), gardem cress (lepidium sativum) and tarragon (Artemisia dracuncullus)] cultivated around the Sanandaj city. (Author)

133

Final Report: Planetary Instrument Definition and Design Program (PIDDP) Support Project  

Energy Technology Data Exchange (ETDEWEB)

The results of Sandia National Laboratories' participation in the NASA Planetary Definition and Design Program are summarized. Areas reported include the characterization of large area cadmium zinc telluride spectrometers and the application of simulation techniques to the prediction of device performance. Also investigated was the response of mercuric iodide devices in the region from 1 to 100 KeV. A literature study to determine the status or radiation damage measurements in room temperature semiconductor devices is also reported.

1999-03-01

134

The corrosion resistance of alloy 800  

International Nuclear Information System (INIS)

Basic studies of the oxidation resistance of Fe-Cr binary and Fe-Cr-Ni ternary alloys in pure oxygen have shown that the excellent corrosion resistance of Alloy 800 is explicable in terms of the low defect concentrations and diffusion rates in the oxide forming on alloys of this composition in sufficiently oxidising environments. The performance of Alloy 800 in environments of particular importance to nuclear power generation is briefly reviewed to determine to what extent ideas derived from the basic studies of Fe-Cr-Ni ternary alloys are borne out in practice. The good corrosion resistance of Alloy 800 in steam and CO_2 and, to some extent, in molten salt environments is in agreement with the behaviour of ternary alloys in oxygen. Minor aliovalent alloying additions are only expected to have a significant effect on the ...

135

Study of the influence of alloying additions on the passivity of aluminum. Annual report 1 Dec 89-30 Nov 90  

Energy Technology Data Exchange (ETDEWEB)

Whereas supersaturated aluminum alloys demonstrate enhanced passivity, conventional aluminum alloys spontaneously pit in air-saturated chloride solutions. We have concentrated on three areas: evaluation and characterization of Al-W alloys, which exhibit the best corrosion performance of any alloy system studied to date; characterization of the passive-film structure of Al-Mo alloys; and production and characterization of Al-W and Al-Ta powders, which will be used for compaction into bulk material. Surface analysis of the Al-W passive films formed during polarization show surprising little oxidized solute compared to other alloys. These results indicate that the barrier layer formation and electrostatic repulsion mechanisms used to explain the passivity of other alloys are not involved here. Instead the W may act to stabilize the passive film ...

1991-03-01

136

A comparison of the low-cycle fatigue behavior of Alloy 800 and Alloy 800H  

International Nuclear Information System (INIS)

At 650"0C, the low-cycle fatigue life was essentially the same for the two alloys on the basis of strain amplitude, but Alloy 800H had a longer life on the basis of stress amplitude. A 500"0C, Alloy 800 and 800H exhibited longer fatigue lifetime than at 650"0C, with Alloy 800 exhibiting a 2-3 times longer life than Alloy 800H when compared on the basis of plastic strain range, whereas the difference was less pronounced when compared on the basis of stress amplitude. When a creep effect was introduced either by way of a hold time or a reduced frequency, Alloy 800 exhibited a greater reduction in life than did Alloy 800H. The dislocation structure changed from planar to cellular with increase in strain range, and extensive precipitation of M_2_3C_6 was noted within the grains for Alloy 800H and along grain boundaries for ...

137

Irradiation-assisted stress corrosion cracking in HTH Alloy X-750 and Alloy 625  

International Nuclear Information System (INIS)

In-reactor testing of bolt-loaded compact tension specimens was performed in 360 C water to determine the irradiation-assisted stress corrosion cracking (IASCC) behavior of HTH Alloy X-750 and direct-aged Alloy 625. New data confirm previous results showing that high irradiation levels reduce SCC resistance in Alloy X-750. Heat-to-heat variability correlates with boron content, with low boron heats showing improved IASCC properties. Alloy 625 is resistant to IASCC, as no cracking was observed in any Alloy 625 specimens. Microstructural, microchemical and deformation studies were performed to characterize the mechanisms responsible for IASCC in Alloy X-750 and the lack of an effect in Alloy 625. The mechanisms under investigation are: boron transmutation effects, radiation-induced changes in microstructure and deformation characteristics, and ...

1995-08-06

138

Interrelation between grain boundary characteristics and intergranular stress corrosion cracking of thermally treated alloy 690 and shot peened alloy 800 in high temperature acidic and alkaline solution  

Energy Technology Data Exchange (ETDEWEB)

To clarify the acidic and alkaline Intergranular Stress Corrosion Cracking (IGSCC) mechanism of thermally treated alloy 690 (alloy 690 TT) and shot peened alloy 800 (alloy 800 SP), C-ring tests were conducted in deaerated HCl solutions and in deaerated NaOH solutions at 350degC, compared with the acidic and the alkaline IGSCC susceptibilities of mill-annealed alloy 600 (alloy 600 MA), full-sensitized one (alloy 600 FS) and thermally treated one (alloy 600 TT). Grain boundary characteristics, such as chromium depleted zone and chromium carbide precipitation, were examined using modified Huey test and Transmission Electron Microscopy. Potential-pH diagram for Ni, Cr, Fe-H{sub 2}O system at 350degC was constructed and the solubilities of NiO, Cr{sub 2}O{sub 3} and Fe{sub 3}O{sub 4} were also calculated to evaluate the ...

2001-05-01

139

Interrelation between grain boundary characteristics and intergranular stress corrosion cracking of thermally treated alloy 690 and shot peened alloy 800 in high temperature acidic and alkaline solution  

International Nuclear Information System (INIS)

To clarify the acidic and alkaline Intergranular Stress Corrosion Cracking (IGSCC) mechanism of thermally treated alloy 690 (alloy 690 TT) and shot peened alloy 800 (alloy 800 SP), C-ring tests were conducted in deaerated HCl solutions and in deaerated NaOH solutions at 350degC, compared with the acidic and the alkaline IGSCC susceptibilities of mill-annealed alloy 600 (alloy 600 MA), full-sensitized one (alloy 600 FS) and thermally treated one (alloy 600 TT). Grain boundary characteristics, such as chromium depleted zone and chromium carbide precipitation, were examined using modified Huey test and Transmission Electron Microscopy. Potential-pH diagram for Ni, Cr, Fe-H_2O system at 350degC was constructed and the solubilities of NiO, Cr_2O_3 and Fe_3O_4 were also calculated to evaluate the stability of oxide films which ...

2001-05-01

141

Stress Corrosion Cracking Susceptibility of Beta Titanium Alloy 38-6-44: Candidate Alloy for Scout Torsion Bar.  

Science.gov (United States)

The threshold stress itensities for stress corrosion crack propagation in beta titanium alloy 38-6-44, Ti-3Al-8V-6Cr-4Mo-4Zr, has been determined in salt water and methanolic solutions. The alloy was immune to stress corrosion cracking in aqueous sodium c...

1974-01-01

142

Review of the corrosion resistance properties of Alloy 800 in high-temperature steam  

International Nuclear Information System (INIS)

The investigations carried out on Alloy 800 in aqueous high-temperature environments in France as well as in other countries are reviewed. These studies are mainly concerned with nuclear industry where Alloy 800 can be used as structural material for steam generators of PWR, breeders or HTR. As results referred to in the literature on cracking in caustic environmens do not always agree, a discussion is presented on the matter. The behaviour of Alloy 800 in superheated steam is examined. (Auth.).

143

Reactivity of ceramic superconductors with palladium alloys  

Science.gov (United States)

This paper reports Palladium alloy compositions investigated for suitability as a nonreactive material for the processing of ceramic superconductors. Barium-based superconductors were tested on Pd-Au and Pd-Ag alloys for reactivity. Bismuth-based superconductors were tested on a Pd-Ag alloy. The least reactive was found to be 70% Pd-30% Ag for the barium-based high-temperature superconductors (HTSC), whereas 30% Pd-70% Ag was found to be least reactive for bismuth-based HTSC.

1990-06-01

144

Postweld aging of a metastable beta-titanium alloy  

International Nuclear Information System (INIS)

(Nov 1973). United States Greenfield, MA Pierce, CM Chicago, IL.

145

Modification of surface properties of copper-refractory metal alloys  

Energy Technology Data Exchange (ETDEWEB)

The surface properties of copper-refractory metal (CU-RF) alloy bodies are modified by heat treatments which cause the refractory metal to form a coating on the exterior surfaces of the alloy body. The alloys have a copper matrix with particles or dendrites of the refractory metal dispersed therein, which may be niobium, vanadium, tantalum, chromium, molybdenum, or tungsten. The surface properties of the bodies are changed from those of copper to that of the refractory metal.

1993-10-12

148

Investigation of Destruction Mechanisms in Reactor Steels  

International Science & Technology Center (ISTC)

Investigation of Destruction Mechanisms in Reactor Steels and Alloys under Cycling Deformation

152

General corrosion of ALLOY 800 in high temperature water and its prevention  

Energy Technology Data Exchange (ETDEWEB)

General corrosion behavior of ALLOY 800 in high temperature water was studied in relation to its surface film structure. The surface film formed in water was found to decrease the corrosion rate of ALLOY 800. This film is composed of Ni ferrite, and can be obtained by oxidation in air or steam. Based on these results, air or steam oxidation treatment to inhibit Ni and Co release of ALLOY 800 into high temperature water is proposed. (author).

1989-10-01

153

General corrosion of ALLOY 800 in high temperature water and its prevention  

International Nuclear Information System (INIS)

General corrosion behavior of ALLOY 800 in high temperature water was studied in relation to its surface film structure. The surface film formed in water was found to decrease the corrosion rate of ALLOY 800. This film is composed of Ni ferrite, and can be obtained by oxidation in air or steam. Based on these results, air or steam oxidation treatment to inhibit Ni and Co release of ALLOY 800 into high temperature water is proposed. (author).

156

Effect of aging on the pitting corrosion behavior in Al-Li alloys  

Energy Technology Data Exchange (ETDEWEB)

In the present work, electrochemical measurements and corrosion tests in NaCl solutions were carried out to study the effect of aging treatments on pitting corrosion behavior in a 8090 alloy and its high purity Al-Li binary alloy analogue. The pitting corrosion characteristics and corrosion resistance of the 8090 alloy have been determined in relation to precipitation microstructures. (orig.).

1990-06-01

158

EFFECT OF MICROSTRUCTURE ON THE STRENGTH ...  

Science.gov (United States)

... THE STRENGTH, TOUGHNESS, AND STRESS-CORROSION CRACKING SUSCEPTIBILITY OF A METASTABLE BETA TITANIUM ALLOY (Ti-11. ...

1970-02-01

159

Direct production of niobium titanium alloy during niobium reduction  

International Nuclear Information System (INIS)

This paper describes a process for the direct production of a superconductive niobium-titanium alloy during reduction of niobium pentoxide. It comprises: mixing at least one of titanium metal powder and titanium dioxide powder with niobium pentoxide powder and aluminum powder; heating the resulting mixture to form a niobium-titanium alloy and a slag consisting essentially of aluminum oxide; and separating the alloy and the slag.

1989-10-26

160

Development of zirconium alloys. Part II  

Science.gov (United States)

A number of alloys of zirconium have been investigated as part of a program aimed at improving the high-temperature tensile and creep strength of zirconium. These alloys include aluminum, beryllium, lead, magnesium, molybdenum, niobium, tantalum, tin, titanium, tungsten, vanadium, and zinc, binary and ternary alloys. The data indicate that aluminum, lead, molybdenum niobium, tin, titanium, tungsten, and vanadium can be used successfully to harden zirconium, and that aluminum, tin, titanium, and vanadium are particularly effective in maintaining the strength of zirconium at elevated temperatures.

1952-01-02

161

Corrosion resistance of zinc coatings on depleted uranium and uranium alloys  

Energy Technology Data Exchange (ETDEWEB)

Simulated atmospheric corrosion studies were performed to determine the corrosion protection provided by galvanized zinc coatings on depleted uranium, U-0.75 Ti alloy, and U-6 Nb alloys. The accelerated ASTM tests consisted of exposing the galvanized samples to aqueous and aqueous chloride environments. The test results showed that anodic protection was provided by the electronegative zinc coatings on uranium and uranium alloys. Treating zinc with chromate conversion coatings also provided more protection.

1985-01-27

162

Carbon effect on the structure and plasticity characteristics of titanium #beta#-alloys  

International Nuclear Information System (INIS)

In this paper a study is made of the structure and mechanical properties of the #beta# alloy system Ti-Mo-Zr-Sn (the composition of which is equivalent to the #beta# III alloy used abroad) containing different amounts of carbon. Study of the #beta#-titanium alloy containing 0.1% C revealed the presence of particles of titanium carbide. Separation of the titanium carbide promotes a reduction in impact strength, an increased tendency toward cold shortness, and poorer workability. (author).

163

Ultra high strength beta titanium alloy for fasteners  

International Nuclear Information System (INIS)

A new high strength titanium alloy has been developed primarily intended for fastener applications. While Ti-6Al-4V is used extensively as a fastener alloy in the aerospace industry, its shear strength allowable is limited to 655 MPa (95 ksi). For higher shear strength requirements, various steels or nickel-based alloys are used (up to 860 MPa (125 ksi)), but with the attendant density penalty. This new alloy is intended to provide the 860 MPa shear strength at roughly a 40% weight savings. After screening various alloy systems, the optimum chemistry has been selected as follows: Ti-6.0V-6.2Mo-5.7Fe-3Al. In light of its 125 ksi shear strength goal, the alloy has been designated TIMETAL reg-sign 125.

1993-02-21

164

Tensile properties and bending formability of drawn magnesium alloy pipes  

Energy Technology Data Exchange (ETDEWEB)

Magnesium alloys are being increasingly utilized in a variety of fields as an alternative material to organic materials and aluminum alloys, owing to excellent properties. Those include low density, and excellent damping properties. When compared to organic materials, furthermore, Mg alloy excels at recyclability, heat radiation, and electromagnetic-shielding. Though most of magnesium alloy products are manufactured through die-casting and thixo-molding at present, the demand for the expanding of magnesium wrought alloy market is increasing. Taking full advantage of a drawing technique and applying it to the conventional extruded pipe, we have developed a new type of magnesium alloy pipe. The strength of the developed pipe is significantly higher than that of the conventional one, either extruded or die-casting. Some of the excellent properties were obtained ...

2003-07-01

165

Production of powder titanium alloys with Mo, Zr, Nb additions and their properties  

International Nuclear Information System (INIS)

In order to substitute expensive cast titanium alloys by powder ones the possibility of introduction of powder additions by mechanical stock mixing is studied. It is shown that microstructure of powder alloys of Ti-Zr(1-9%) system is typical for one-phase cast #alpha#-alloys. The Ti-Mo(1-9%) and Ti-Nb(1-9%) system alloys have microstructure typical for two-phase (#alpha#+#beta#)-alloys. For homogeneous structure to be obtained the high temprature annealing is advisable after hot pressing. Alloying with Mo, Zr and Nb permits to increase considerable the strength of powder titanium products (at 9% Mo more than two times).

166

Passivity of high corrosion resistant Cu-Al-Sn alloys  

Energy Technology Data Exchange (ETDEWEB)

In a work studying the corrosion and tarnishing properties of a variety of copper alloys, the alloy Cu-A110-Sn5 was found to show an excellent corrosion resistance in neutral solutions, where copper and most conventional Cu alloys are covered by thick nonprotective surface layers. The passive films formed on this alloy were characterized with electrochemical and photoelectrochemical methods. The pH dependence of the passivation and of the photocurrent behavior of the Cu-A110-Sn5 alloy clearly indicates that the passivity of this alloy in neutral solutions is due to a formation of passive film enriched with aluminum oxide. At corrosion potential a strong increase in the corrosion resistance with time is due to a gradual enrichment of the surface with aluminum oxide. This can be seen in the photocurrent spectra which change from cooper-type to aluminum-type with ...

1993-10-01

167

High-temperature property data: Ferrous alloys  

Energy Technology Data Exchange (ETDEWEB)

In this book over 250 alloys are organized by AISI number into 10 major sections: Irons, Carbon Steels, Alloy Steels, Low Alloy Constructional Steels, Ultra High Strength Steels, Tool Steels, Maraging Steels, Wrought Stainless Steels, Heat Resistnat Casting Alloys, and Iron Based Rought Superalloys. Each alloy record lists the designation, specifications, UNS number, composition, product forms and a comment on the high-temperature properties and applications. Referenced data is then given for physical properties such as density, specific heat, thermal conductivity, thermal expansion, electrical conductivity, Poisson's ratio, moduli of elasticity and rigidity, etc. Mechanical properties follow, and include tensile properties, shearing and bearing properties, impact properties, creep, stress rupture and stress relaxation and fatigue properties. The last part of the ...

1987-01-01

168

Fundamental reasons for the good performance of Alloy 800 in nuclear steam generators  

Energy Technology Data Exchange (ETDEWEB)

It is hypothesized that the good performance of Alloy 800 in steam generator service is due to its relative immunity to two distinct mechanisms of stress corrosion cracking; the argument also applies to intergranular corrosion. One mechanism operates in the high-nickel region (Alloy 600 and nearby model alloys) and is due to internal intergranular oxidation. The other operates in the low-nickel (stainless steel) region and is due to de-alloying of Fe and/or Cr. This latter mechanism may, under special conditions, operate in high-Ni, high-Cr alloys such as 690. Some essential features of the de-alloying mechanism are demonstrated using strong caustic solutions, and the prospect of extending this approach to dilute high-temperature environments is discussed. (author)

2007-07-01

169

Fatigue of magnesium alloys  

Energy Technology Data Exchange (ETDEWEB)

Magnesium alloys show a high specific strength and are therefore increasingly used for light-weight constructions in transportation industry.{sup [1,2]} To predict the behaviour of the material under the influence of cyclic loading it is vital to understand the fatigue behaviour of magnesium alloys. Only when understood properly, it is possible to fully apply the potential weight reduction by using magnesium alloys. A very important aspect in fatigue of magnesium alloys is the influence of a corrosive media and elevated temperatures, of which both are relevant in automotive applications. These two factors tend to have deleterious effects on magnesium alloys and therefore also have to be considered in investigations on the fatigue behaviour of magnesium alloys. (Abstract Copyright [2004], Wiley Periodicals, Inc.)

2004-05-01

170

Colorimetric analysis of opaque porcelain fired to different base metal alloys used in metal ceramic restorations  

British Library Electronic Table of Contents (United Kingdom)

Statement of problem. The popularity of base metal alloys has considerably increased in recent years because of their superior mechanical properties as well as the high cost of noble alloys. However, there is disagreement about their effect on the opaque porcelain color and the color differences among base metal alloys. Purpose. The purpose of this in vitro study was to determine and compare the influence of various commercially available base metal alloys (excluding titanium-based systems) on the resulting color of opaque porcelain with the use of a colorimetric device. Material and methods. Fourteen different types of Ni-Cr and 3 different types of Co-Cr porcelain bonding alloys were selected with a Au-Pd alloy (V-Delta SF) as the control group for colorimetric measurements and determina...

2008-01-01

171

Summary on performance study of corrosion resistance of zirconium alloys  

International Nuclear Information System (INIS)

Zirconium-base alloys are used primarily as fuel cladding material and other core structure material in water cooled nuclear power reactors. Main research achievements and problems about corrosion of zirconium alloys are reviewed; the present theories and challenge are summarized. In the 1980s, great progress had been made towards correlating alloy composition, microstructure and irradiation with corrosion resistance. In the 1990s, main researches are focused on exploring actual mechanism of corrosion, optimizing both alloy composition and microstructure in order to minimize the fuel cycle costs through burnup optimization.

172

Stress corrosion cracking susceptibility of #beta# titanium alloy 38-6-44  

International Nuclear Information System (INIS)

The threshold stress intensities for stress corrosion crack propagation in beta titanium alloy 38-6-44, Ti3Al-8V-6Cr-4Mo-4Zr, has been determined in salt water and methanolic solutions. The alloy was immune to stress corrosion cracking (SCC) in aqueous sodium chloride solutions (marine atmosphere). However, in methanolic solutions, the alloy was very susceptible to SCC. This marked susceptibility in methanolic solutions can be mitigated by the addition of an inhibitor: sodium nitrate. Crack extension in the alloy was transgranular and failure occurred by brittle quasi-cleavage in methanolic solutions.

173

SP-700 titanium alloy data sheets  

International Nuclear Information System (INIS)

SP-700, an emerging #beta#-rich #alpha#+#beta# titanium alloy, is designed to improve superplastic formability as well as mechanical properties over Ti-6Al-4V alloy. Owing to its fine microstructure and low #beta#-transus temperature, it is superplastic-formable at temperature below 1,073K (800 C) with low flow stress. Remarkable workability of this alloy is also retained in conventional Manufacturing processes. Another advantage of SP-700 is heat treatment response which includes deep hardenability and quick aging kinetics. Corrosion resistance and machinability are equivalent to or better than Ti-6Al-4V alloy.

1993-02-21

174

Quench effect on mechanical properties and structure of the TS6 #beta#-titanium alloy  

International Nuclear Information System (INIS)

By the methods of microstructural and electron-microscopic analyses by the tension test and impact test studied is the effect of quenching conditions on structure and mechanical properties of the TS6 titanium-#beta# alloy. It is shown that low temperature quenching from 700 deg C, recommended earlier for analogous VT15 titanium alloy, leads to appearence of intercrystalline fracture and to sharp decrease of impact strength of the TS6 alloy. Established are optimum conditions for quenching of half-finished products and articles of the TS6 alloy depending on their subsequent working or operation.

175

Nature of the magnetic susceptibility of dysprosium. Paramagnetic susceptibility of dysprosium - yttrium alloys  

International Nuclear Information System (INIS)

The paramagnetic susceptibility of single crystals of dysprosium-yttirum alloys is measured in the basal plane and along the hexagonal axis. It is shown that the susceptibility of the alloys obeys the Curie-Weiss law, the effective magnetic moments allong the different directions being the same and the paramagnetic Curie temperatures being different. The difference between the paramagnetic Curie temperatures in the basal plane and along the hexagonal axis is independent of the dysprosium concentration in the alloy. As a comparison with the theoretical models of magnetic anisotropy shows, this is an indication that the magnetic anisotropy of dysprosium - yttrium alloys is of a single-ion nature.

1976-01-01

176

Mechanisms of Alloy 800 corrosion in helium  

International Nuclear Information System (INIS)

Cr_2O_3 scales are found to form on Alloy 800 and a similar pure ternary alloy in air, and 1 and 50 atm. helium containing oxidizing impurities typical of those in an SGHTR. The strong temperature dependence and neglibible helium overpressure dependence indicate that gas transport through the scales is not rate controlling. Surface oxidation rates are therefore controlled by solid state diffusion and the low oxygen partial pressure dependence of the oxidation rate in Alloy 800 is ascribed to the presence of extrinsic defects in the Cr_3O_3 (due to doping by alloying elements) or to the presence of short circuit diffusion paths. (Auth.).

177

Friction stir welding of dissimilar formed Mg alloys (AZ31/AZ91)  

Energy Technology Data Exchange (ETDEWEB)

Friction stir welding of dissimilar formed Mg alloys(AZ31/AZ91) was successfully carried out at the limited welding conditions. In a sound joint, SZ was mainly consisted of AZ31 Mg alloy which was located the retreating side. Dynamic recrystallization and grain growth occurred and {beta} intermetallic compounds of AZ 91 Mg alloy was not observed in SZ. BM had a higher hardness than that of the weld zone. The fracture location was not weld zone but BM of the AZ91 Mg alloy in tensile test. (orig.)

2005-07-01

178

Time-temperature-precipitation and time-temperature-sensitization behavior of highly corrosion resistant nickel-chromium-molybdenum alloys. Das Zeit-Temperatur-Ausscheidungs- und das Zeit-Temperatur-Sensibilisierungs-Verhalten von hochkorrosionsbestaendigen Nickel-Chrom-Molybdaen-Legierungen  

Energy Technology Data Exchange (ETDEWEB)

The time-temperature-precipitation diagrams and the resulting time-temperature-sensitization diagrams have been established and are presented for today's current nickel-chromium-molybdenum alloys C-4, C-276, 22 and the recently developed alloy 59. Compared to those materials alloy 625 behaves differently due to its high niobium content. In addition, also the precipitation and sensitization of alloy G-3 has been established. Under the materials considered alloy C-276 has the strongest tendency to precipitate the intermetallics Mu and P together with the carbide M{sub 6}C at intermediate temperatures, followed by the alloys 22 and 59. The tendency to sensitization in the sense of the 50{mu}m (2 mils) intercrystalline penetration criterion when exposed to the ASTM G-28, method A test solution is greatest with alloy C-276, and decreases ...

1992-05-01

179

The effect of age hardening on creep crack growth in alloy 800  

International Nuclear Information System (INIS)

The creep crack growth properties of two versions of Alloy 800 have been compared at 500 and 600"0C in the Grade II condition in tests up to 10"4 hours duration. The two alloys were a low carbon alloy containing (wt.%) 0.024 C, 0.5 Ti, 0.3 Al (Alloy B) and a higher carbon alloy containing (wt.%) 0.038 C, 0.2-0.3 Ti, 0.2-3.0 Al (Alloy J). At 600"0C, Alloy B attained maximum age hardening in 10"2 hours, whereas J did not harden significantly in time up to 10"4 hours. Both alloys age hardened at 550"0C with Alloy J hardening more rapidly than B. The creep displacements and displacement rates in small compact tension specimens at 600"0C were smaller than Alloy B than in Alloy J. However, failure times were shorter in Alloy B because of lower ...

180

Investigation on corrosion and wear behaviors of nanoparticles reinforced Ni-based composite alloying layer  

Energy Technology Data Exchange (ETDEWEB)

In order to investigate the role of amorphous SiO{sub 2} particles in corrosion and wear resistance of Ni-based metal matrix composite alloying layer, the amorphous nano-SiO{sub 2} particles reinforced Ni-based composite alloying layer has been prepared by double glow plasma alloying on AISI 316L stainless steel surface, where Ni/amorphous nano-SiO{sub 2} was firstly predeposited by brush plating. The composition and microstructure of the nano-SiO{sub 2} particles reinforced Ni-based composite alloying layer were analyzed by using SEM, TEM and XRD. The results indicated that the composite alloying layer consisted of {gamma}-phase and amorphous nano-SiO{sub 2} particles, and under alloying temperature (1000 deg. C) condition, the nano-SiO{sub 2} particles were uniformly distributed in the alloying layer and still kept the amorphous structure. ...

2008-04-30

181

Investigation on corrosion and wear behaviors of nanoparticles reinforced Ni-based composite alloying layer  

International Nuclear Information System (INIS)

In order to investigate the role of amorphous SiO2 particles in corrosion and wear resistance of Ni-based metal matrix composite alloying layer, the amorphous nano-SiO2 particles reinforced Ni-based composite alloying layer has been prepared by double glow plasma alloying on AISI 316L stainless steel surface, where Ni/amorphous nano-SiO2 was firstly predeposited by brush plating. The composition and microstructure of the nano-SiO2 particles reinforced Ni-based composite alloying layer were analyzed by using SEM, TEM and XRD. The results indicated that the composite alloying layer consisted of ?-phase and amorphous nano-SiO2 particles, and under alloying temperature (1000 deg. C) condition, the nano-SiO2 particles were uniformly distributed in the alloying layer and still kept the amorphous structure. The corrosion resistance of composite ...

2008-04-30

182

Novel alloys to improve the electrochemical behavior of zinc anodes for zinc/air battery  

Energy Technology Data Exchange (ETDEWEB)

In our continued efforts for improving the performance of zinc anodes for a Zn/air battery, we now report the preparation of three alloys and improved performances of anodes made up with these alloys. The alloys contained zinc, nickel, and indium with different weight percentages and were calcined at two different temperatures. Out of the six alloys, the alloy which has a composition of zinc 90%, nickel 7.5% and Indium 2.5% and fired at 500{sup o}C is found to be the best. In the case of the hydrogen evolution reaction, this alloy had its potential shifted to a more negative potential. As far as the cyclic voltammograms were concerned, the difference between the anodic and cathodic part was minimal when compared with other alloys. Surprisingly, this alloy had reversibility even after 100 cycles of the cyclic ...

2006-10-06

183

Hydrogen embrittlement of Ni-Cr-Fe alloys  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this work was to investigate the role of chromium on hydrogen embrittlement of Ni-Cr-Fe alloys and thus to develop a better understanding of the low-temperature stress corrosion cracking (SCC) phenomenon. The effect of chromium on hydrogen embrittlement was examined using tensile tests followed by material evaluation via scanning electron microscopy (SEM) and light optical microscopy. Four alloys were prepared with chromium contents ranging from 6 to 35 wt pct. In the uncharged condition, ductility, as measured by the percent elongation or reduction in area, increased as the alloy chromium content increased. Hydrogen appeared to have only minor effects on the mechanical properties of the low-chromium alloys. The addition of hydrogen had a marked effect on the ductility of the higher-chromium alloys. In the 26 pct chromium alloy, the elongation to ...

1997-03-01

184

High temperature fatigue damage in three austenitic alloys  

Energy Technology Data Exchange (ETDEWEB)

A series of cyclic strain controlled tests have been carried out at 600/sup 0/C on three high temperature austenitic iron-based alloys, AISI type 316 stainless steel, Alloy 800 H and Sandvik 253 MA. The tests were carried out under constant total strain control using a constant strain rate of 0.005 s/sup -1/. By considering the changes in modulus throughout the life of each specimen it was found that damage evolution could be successfully predicted as a function of plastic strain range despite the fact that each alloy had been chosen because of a different stress response at 600/sup 0/C. Although each alloy accumulated fatigue damage in a similar manner the longer lives of Sandvik 253 MA and Alloy 800 H at a given total strain range were due to a smaller plastic strain component and a reduced stage I crack propagation rate. In the 253 MA alloy, slip was ...

1988-01-01

185

Dislocation-enhanced hydrogen solubilities in Pd-Ni, Pd-Ag and Pd-Ni-Ag alloys  

Science.gov (United States)

The purpose of this communication is to determine whether the solubility enhancements for cold-worked Pd-Ni alloys increase or decrease with atom fraction of Ni. Substitutional Ni atoms contract and Pd lattice, in contrast to the lattice expansion resulting from substitutional Ag in Pd. The Pd-Ni alloy system forms a continuous series of fcc solid solution alloys over the whole composition range. The solubility enhancements will also be determined for a series of homogeneous, ternary Pd[sub 1[minus]x]Ni[sub 1/2x]Ag[sub 1/2x] alloys for x in the range from 0 to 0.2. For this series of ternary alloys the fcc lattice parameters do not change significantly from that of pure Pd. The alloys used in this research were purchased from Tanaka Kikinzoku Kogyo K.K. The detailed experimental procedure has been described previously. The alloys were all ...

1994-03-01

186

Alternate alloying for environmental resistance; Proceedings of the Symposium, New Orleans, LA, Mar. 2-6, 1986  

Energy Technology Data Exchange (ETDEWEB)

Papers are presented on the development of oxidation- and sulfidation-resistant ferritic alloys; the microstructural stability of sulfidation-resistant FeCrAl stainless steels around 500 C; age hardening in Fe-Mn-Al-C austenitic alloys; the oxidation/corrosion behavior of low-Cr Fe-Cr-Ni alloys containing Zr or Nb; the high temperature oxidation/corrosion of iron-based superalloys; and the role of Mo in the Na/sub 2/SO/sub 4/ induced corrosion of superalloys at high temperature. Topics discussed include the effect of variations of Co content on the cyclic oxidation resistance of selected Ni-base superalloys; high temperature oxidation of Fe based alloys; the morphological development of high temperature oxide scales of Fe-Mn-Al base alloys; and the oxidation of an Fe-Mn-Al-C alloy at 1000 C. Consideration is given to the corrosion properties of Fe-Mn-Al ...

1987-01-01

187

Suppressive effects of cadmium on neurons and affected proteins in cultured developing cortical cells  

International Nuclear Information System (INIS)

The purpose of the present study was to examine the in vitro effects of low-dose cadmium (Cd) on developing cortical cells. The cortical cells removed from fetuses (embryonic day 15) were treated with 10 nM of Cd for 24 h. The effects of Cd on dendritic and synaptic development were immunocytochemically observed with anti-microtubule associated protein-2 (MAP2) and anti-synapsin I antibodies, respectively. Administration of Cd suppressed dendritic as well as synaptic development at 10 nM. By two-dimensional gel electrophoresis and liquid chromatography-tandem mass spectrometric (LC/MS/MS) analysis, we identified three proteins with different expression after Cd-treatment; dihydropyrimidinase-related protein 2 (DRP-2/CRMP-2), 14-3-3-epsillon and calmodulin (CaM). Though the number of identified proteins was small, these proteins are known to be involved in neuronal development. The present study demonstrated the morphological effects as well as affected proteins in ...

2008-11-20

188

Spectroscopic properties of Er"3"+ ions in cadmium and alkali cadmium borosulphate glasses  

International Nuclear Information System (INIS)

Spectroscopic properties of Er"3"+ : CBS (CdSO_4 + B_2O_3 and R_2SO_4 + CdSO_4 + B_2O_3, R_2SO_4 = Li_2SO_4.H_2O, Na_2SO_4, K_2SO_4 and Gd_2(SO_4)_3.8H_2O) glasses are reported. The assigned energy level data of Er"3"+(4f"1"1) in these glasses are analysed in terms of a parametrized model Hamiltonian. The standard deviations of the data fits are between 39 and 47 cm"-"1 so that the energy level schemes of the Er"3"+(4f"1"1) ions in borosulphate (CBS) glasses are reasonably well reproduced. Radiative properties for the fluorescent levels of Er"3"+ : CBS glasses are determined by using the Judd-Ofelt theory. The potential laser transitions are identified with the help of predicted radiative properties which are compared and discussed with similar results. (author).

1997-01-01

189

Recent Progress in CdTe and CdZnTe Detectors  

CERN Document Server

Cadmium telluride (CdTe) and cadmium zinc telluride (CdZnTe) have been regarded as promising semiconductor materials for hard X-ray and Gamma-ray detection. The high atomic number of the materials (Z_{Cd} =48, Z_{Te} =52) gives a high quantum efficiency in comparison with Si. The large band-gap energy (Eg ~ 1.5 eV) allows us to operate the detector at room temperature. However, a considerable amount of charge loss in these detectors produces a reduced energy resolution. This problem arises due to the low mobility and short lifetime of holes. Recently, significant improvements have been achieved to improve the spectral properties based on the advances in the production of crystals and in the design of electrodes. In this overview talk, we summarize (1) advantages and disadvantages of CdTe and CdZnTe semiconductor detectors and (2) technique for improving energy resolution and photopeak efficiencies. Applications of these imaging detectors in ...

2001-01-01

190

Preparation of immission dust samples for the analysis of toxic substances in dust by atomic emission spectroscopy with inductively coupled plasma  

International Nuclear Information System (INIS)

Samples of air-dust-concentration- and air-dust-deposit measurements were digested by a standardized wet digestion procedure and the amounts of substances in the dust according to class I TA Luft by Atomic Emission Spectroscopy with Inductively Coupled Plasma (AES-ICP). The characteristic values for procedures according to VDI 2449, sheet 1, were determined for lead, vanadium, cadmium, chromium, copper, nickel and zinc. By partial automatic control of the digestion procedure the personel expenditure of work could be reduced by a factor 13. Dust filter samples were analysed without sample preparation by evaporating the material with a solid state laser. The absolute detection limit was between 1 and 100 ng/cm"2 for the elements arsenic, cadmium, cobalt, chromium, mercury, antimony, selen and thallium. For sampling by means of the Beta-Staubmeter the relative detection limits for the laser-ICP were 10-fold lower than by use of a nebulizer. ...

191

Microprocessor-controlled anodic stripping voltammeter for trace metal analysis in tap water  

Energy Technology Data Exchange (ETDEWEB)

The construction and use of a portable, microprocessor controlled anodic stripping voltameter for on-site simultaneous metal analysis of copper, lead and cadmium in tap water is discussed. The instrumental system is comprised of a programmable controller which permits keying in analytical parameters such as sparge time and plating time: a rotating cell for efficient oxygen removal and amalgam formation; and, data handling via a minicomputer or analog pen recorder. Plating and stripping potentials are controlled by a digital potentiostat; stripping is done using a staircase waveform with measurement of the current after a one msec delay. In this way charging current effects are minimized. Results of tap water analysis showed 3 +- 1 ..mu..g/L lead, 22 +- 0.3 ..mu..g/L copper, and less than 0.2 ..mu..g/L cadmium for a Berkeley, California tap water, and 1-1000 ..mu..g/L Cu, 1 -2 ..mu..g/L Pb for ten samples of Seattle, Washington tap water. ...

1984-06-01

192

High power nickel - cadmium cells with fiber electrodes (FNC)  

International Nuclear Information System (INIS)

Nickel cadmium batteries differ greatly in their mechanical design and construction of the electrodes. Using available electrode constructions, batteries are designed which meet the requirements of specific applications and offer optimum performance. Pocket- and tubular cells are basically developed with the technology of the year 1895. Since then some improvements with todays technology have been made. The sintered cells use the technology of the 1930's and they are still limited to high power application. With this knowledge and the technology of today the fiber-structured nickel electrode (FNC) was developed at DAUG laboratory, a subsidiary company of Mercedes-Benz and Volkswagen. After ten years of experience in light weight prototype batteries for electric vehicles (1-2), the system was brought into production by a new company, DAUG-HOPPECKE. Characteristics of fiber electrodes: thickness and size can be easily changed; pure active materials are used; high ...

193

Experimental Evaluation And Simulation Of Multi-pixel Cadmium-zinc-telluride Hard-x-ray Detectors  

CERN Document Server

This dissertation describes the evaluation of many-pixel Cadmium-Zinc-Telluride (CdZnTe) hard-X-ray detectors for future use with the High Energy Replicated Optics (HERO) telescope being developed at Marshall Space Flight Center. The detector requirements for the HERO application are good energy resolution (sufficient to resolve cyclotron features and nuclear lines), spatial resolution of ∼200 μm, minimal charge loss of absorbed X rays, and minimal sensitivity to the background environment. This research concentrates on assessing the suitability of these detectors for the focus of HERO, and includes the development of a simulation of the physics involved in an X-ray-detector interaction, a study of the intrinsic material properties, measurements with prototype detectors such as the energy and spatial resolution, charge loss, and X-ray background reduction through 3-dimensional depth sensing. Two types of detectors were available for evaluation. The ...

2004-01-01

194

Apoferritin Templated Synthesis of Metal Phosphate Nanoparticle Labels for Electrochemical Immunoassay  

Energy Technology Data Exchange (ETDEWEB)

W have introduced template-synthesized metal phosphate nanoparticle labels for electrochemical immunoassay. Such use of an apoferritin template offers a simple and convenient route to prepare metallic nanoparticle labels for electrochemical immunoassays and avoid the complicated and time-consuming nanoparticle synthesis process (QD synthesis). Releasing metal ions from metal phosphate in an acetate buffer (pH 4.6) eliminates the harsh condition in the traditional metallic nanoparticle dissolution (e.g., strong acid dissolution of QDs and gold nanoparticles). This method is ultrasensitive and its DL is low to 77fM. The simultaneous detection of multiple protein targets is easily performed by using different metal phosphate nanoparticle labels (cadmium phosphate and lead phosphate). This approach can be extended to prepare multiple metal (such as zinc, lead, cadmium, copper, indium, gold, silver) phosphate nanoparticle labels or hybrid metal ...

2006-08-29

195

A 1500-year record of lead, copper, arsenic, cadmium, zinc level in Antarctic seal hairs and sediments  

Energy Technology Data Exchange (ETDEWEB)

To reconstruct the profiles of heavy metal levels in the South Ocean ecosystem of Antarctica, the concentrations of lead (Pb), copper (Cu), arsenic (As), cadmium (Cd), and zinc (Zn) in seal hairs and lake sediments spanning the past 1500 years from Fildes Peninsula of King George Island and in weathering lake sediments from Nelson Island of West Antarctica were determined. The lead contents in the seal hairs and the weathering sediments show a sharp increase since the late 1800s, very likely due to anthropogenic contamination from modern industries. After the 1980s, the Pb content in seal hairs dropped by one-third, apparently due to the reduced usage of leaded gasoline in the Southern Hemisphere. Copper arises mainly from the weathering process, and its level may be substantially affected by climatic conditions. The concentrations of Cd, As, and Zn do not show any clear temporal trends.

2006-12-01

196

Trace metals in tap water from Tehran, Iran  

Energy Technology Data Exchange (ETDEWEB)

A total of 272 tap water samples were collected from 68 homes throughout the city of Tehran. Analysis for cadmium, zinc, lead, copper, arsenic, iron and manganese showed some accumulation of these metals in household piping overnight. However, the concentration of all metals was in the parts per billion (ug/l) range and well below international standards. Heavy metals in Tehran's drinking water therefore, do not pose a significant acute health hazard. 19 references, 2 tables.

1986-01-01

197

Synthesis of CdSe nanoparticles and their effect on the antioxidant activity of Spirulina platensis and Porphyridium cruentum cells  

International Nuclear Information System (INIS)

Single-crystalline cadmium selenide nanoparticles were obtained using high-temperature solution phase synthesis (HTSPS) synthesis. X-Ray powder diffraction and transmission electron microscopy were used to confirm the crystallinity and morphology of the resulting nanoparticles. To study the action of CdSe on antioxidant activity, we selected two biotechnological important strains of microalgae: cyanobacteria Spirulina platensis and red microalgae Porphyridium cruentum. In the case of Porphyridium cruentum, the obtained results demonstrated an increase in the productivity. For Spirulina platensis, the presence of the compound in the cultivating medium decreased the productivity of cyanobacteria.

2011-07-07

198

Synthesis and characterization of nickel(II), chromium(III), cobalt(II), copper(II), zinc(II), and cadmium(II) complexes with isatin- isonicotinoylhydrazone  

International Nuclear Information System (INIS)

A few metal complexes of isatin-isonicotinoylhydrazone with Ni(II), Cr(III), Co(II), Cu(II), Zn(II) and Cd(II) have been prepared and characterized on the basis of elemental analyses, infrared and electronic spectra as well as "1H NMR spectra, conductivity and magnetic measurements. In view of the results obtained, it has been found that two molecules of isatin-isonicotinoylhydrazone are chelated to the central metal ion as bis-uninegative ONO tridentate ligand forming non-electrolytic octahedral metal complexes. (author)

1997-03-01

199

Probable role of trace elements of some medicinal plants in cardio-vascular diseases  

International Nuclear Information System (INIS)

A number of herbal drugs are used in the Unani (Greco-Arab) System of Medicine for cardiovascular diseases. The herbs were analyzed by flame AAS and ICP-AES to determine if their therapeutic actions can be associated with the elements present in them. Cadmium, cobalt, chromium, copper, iron, potassium, magnesium, manganese, sodium, nickel, phosphorus, lead and zinc were some of the elements which play various roles in cardiovascular affections. An effort was made to correlate the role of these elements in cardiac diseases. (Auth.). 2 tabs., 32 refs.

200

Determination of uranium and thorium concentrations in integrated circuit packaging materials  

International Nuclear Information System (INIS)

The purpose of the present research is to find a suitable technique to measure trace amounts of uranium and thorium and to determine the surface #alpha#-flux in silicon compound (SiO) used for fabrication of integrated circuit packaging materials. Among several commonly-used detecting techniques, it was found that neutron activation analysis (NAA) was most promising. The results from NAA show a large difference in uranium and thorium concentrations when cadmium and boron carbide shields are used, whereas #alpha#-flux measurements show a low #alpha#-activity, which corresponds to the trace amounts of uranium and thorium expected to be present in these materials. (author) 13 refs.; 6 figs.

201

Analytical methods for heavy metals in herbal medicines  

British Library Electronic Table of Contents (United Kingdom)

Abstract Introduction - It is estimated that about 70-80% of the world's population relies on non-conventional medicine, mainly of herbal origin. However, owing to the nature and sources of herbal medicines, they are sometimes contaminated with toxic heavy metals such as lead, arsenic, mercury and cadmium, which impose serious health risks to consumers. It is critical to analyse source materials for heavy metals in order to ensure that their concentrations meet the related standards or regulations limiting their concentrations in herbal medicines. In this review, different analytical methods for analysis of heavy metals in herbal medicines are discussed. Objective - To provide a comprehensive review of the current state of the art in analytical methods used to detect heavy metals in herbal...

2011-01-01

202

An application of the analysis of variance of measures repeated in an experiment with heavy metals  

International Nuclear Information System (INIS)

A revision of some basic concepts related to the analysis of variance of repeated measures is presented within an ecological context topics such as the types of experiments in which the technique is applicable, the hypotheses of interest, and its preference over other traditional techniques such as regression and conventional analysis of variance, are discussed. As an example, the technique was successfully applied to an experiment carried out at Cienaga Grande de Santa Marta, Colombia, in which the concentration of cadmium #mu#g/g in leaves of the black mangrove Avicennia germinans was measured in several monitoring stations and throughout several sampling intervals representing seasons.

1997-11-01

203

Specific features of radiation damage in titanium alpha-alloys  

International Nuclear Information System (INIS)

Titanium base 'alpha'-alloys (Pt-7M, RK-20 and Ti-5Al-2Zr-1.5V) are considered for their behaviour under neutron irradiation. The role of alloying elements in radiation hardening is discussed depending of neutron fluence and irradiation temperature. For PK-20 alloy three stages of change in mechanical properties are revealed which are following: incubation period and weak hardening, intense radiation hardening, radiation hardening attenuation. Irradiation temperature rise results in an increase of incubation period and threshold neutron fluence. A special attention is paid to hydrogen absorption in #alpha#-titanium alloys under irradiation. It is concluded that titanium base 'alpha'-alloys are serviceable as structural materials in nuclear plants with allowance made for peculiar features of their radiation behaviour. 4 refs.; 7 figs.; 1 tab.

204

Protective nitride formation on stainless steel alloys for proton exchange membrane fuel cell bipolar plates  

British Library Electronic Table of Contents (United Kingdom)

Gas nitridation has shown excellent promise to form dense, electrically conductive and corrosion-resistant Cr-nitride surface layers on Ni-Cr base alloys for use as proton exchange membrane fuel cell (PEMFC) bipolar plates. Due to the high cost of nickel, Fe-base bipolar plate alloys are needed to meet the cost targets for many PEMFC applications. Unfortunately, nitridation of Fe-base stainless steel alloys typically leads to internal Cr-nitride precipitation rather than the desired protective surface nitride layer formation, due to the high permeability of nitrogen in these alloys. This paper reports the finding that it is possible to form a continuous, protective Cr-nitride (CrN and Cr2N) surface layer through nitridation of Fe-base stainless steel alloys. The key to form a protective Cr...

2007-01-01

205

Phase composition of the VT22-alloy and its cyclic strength  

International Nuclear Information System (INIS)

In connection with the different cyclical strengths of the two-phase (#alpha# + #beta#) titanium alloy in the case of the acicular and rounded formations of the #alpha#-phase, we have studied, employing the X-ray diffraction method, the phase composition of the alloy and the influence of heat treatment upon it. Using the method of electronic fractography, we examined the fractures in samples destroyed by the asymmetric twisting, in order to find out why the durability of the alloy is dependent upon the #alpha# - phase structure. It has been found that in the BT22 alloy, the decay the #beta#-phase may proceed in two ways; either with the formation of the martensite #alpha#'-phase of the acicular shape or with the separation of the non-martensite round-shaped #alpha#-phase. The character of the phase transformations #beta# - #alpha# or #beta#-#alpha#' is, to a considerable extent, the conseguence of the ...

206

On the performance of surface plasmon resonance based fibre optic sensor with different bimetallic nanoparticle alloy combinations  

Energy Technology Data Exchange (ETDEWEB)

In this work, we have investigated the capability of different bimetallic nanoparticle alloy combinations to be used in fibre optic sensors based on the technique of surface plasmon resonance. The metals considered for this analysis are silver, gold, copper and aluminium. The performance of the sensor with different bimetallic nanoparticle alloy combinations is evaluated and compared numerically. The performance is analysed in terms of three parameters: sensitivity, signal-to-noise ratio (SNR) and operating range for the sensing layer refractive index values. On the basis of the comparison and some logistic criteria, the best possible bimetallic alloy combinations along with a requisite alloy composition ratio are predicted. The bimetallic nanoparticle alloy combination is capable of simultaneously providing larger values of sensitivity, SNR and operating range, which is not ...

2008-03-07

207

Nickel base alloys for future steam turbines  

International Nuclear Information System (INIS)

Modern commercial alloys are not suited for future steam turbines of operating temperatures beyond 700 C. #gamma#'-hardened alloys like Waspaloy have good mechanical characteristics but have defects when large batches are melted. #gamma#'/#gamma#''-hardened alloys like Inconel 706, on the other hand, are easy to produce but have insufficient microstructural long-term stability and insufficient creep strength. Mixed crystal solidified alloys like Inconel 617 have excessive yield stress at forging temperatures. Two new alloys were therefore developed. Results so far show that they have good production characteristics but insufficient mechanical characteristics. The reasons for this are currently under investigation. (orig.)

2003-11-28

208

Mechanical properties, fracture surface characterization, and microstructural analysis of six noble dental casting alloys  

British Library Electronic Table of Contents (United Kingdom)

Statement of problem Because noble dental casting alloys for metal ceramic restorations have a wide range of mechanical properties, knowledge of these properties is needed for rational alloy selection in different clinical situations where cast metal restorations are indicated. Purpose The purpose of this study was to compare the mechanical properties and examine both the fracture and polished surfaces of 6 noble casting alloys that span many currently marketed systems. Five alloys were designed for metal ceramic restorations, and a sixth Type GPT has Type IV alloy for fixed prosthodontics (Maxigold KF) was included for comparison. Material and methods Specimens (n=6) meeting dimensional requirements for ISO Standards 9693 and 8891 were loaded to failure in tension using a universal testin...

2011-01-01

209

Irradiation induced dislocation loop and its influence on the hardening behavior of Fe-Cr alloys by an Fe ion irradiation  

International Nuclear Information System (INIS)

Nano indentation analysis and transmission electron microscopy observation were performed to investigate a microstructural evolution and its influence on the hardening behavior in Fe-Cr alloys after an irradiation with 8 MeV Fe4+ ions at room temperature. Nano indentation analysis shows that an irradiation induced hardening is generated more considerably in the Fe-15Cr alloy than in the Fe-5Cr alloy by the ion irradiation. TEM observation reveals a significant population of the a0 dislocation loops in the Fe-15Cr alloy and an agglomeration of the 1/2a0 dislocation loops in the Fe-5Cr alloy. The results indicate that the a0 dislocation loops will act as stronger obstacles to a dislocation motion than 1/2a0 dislocation loops.

2008-11-01

210

IGC/IGSCC and general corrosion behavior of alloy 800 as a PWR S/G tube material  

Energy Technology Data Exchange (ETDEWEB)

Resistance of Alloy 800 as a PWR S/G tube material to IGC/IGSCC and Ni, Co release into water was evaluated as compared with Alloys 600 and 690. The study to improve the resistance to IGSCC and general corrosion was also made, including the effects of shot-peening on the distribution of the residual stress of the U-bent tubes and the susceptibility to SCC, the stabilizing elements on IGC/IGSCC, and prior oxidation on general corrosion. From the results, shot-peened Alloy 800 was estimated to be the most reliable S/G tube material among the high nickel alloys tested. In addition, the Alloy 800 tube would obtain further reliability in IGSCC and general corrosion resistance by the combined addition of Ti, and Nb, and the prior oxidation of the inner tube surface, respectively.

1987-01-01

211

IGC/IGSCC and general corrosion behavior of alloy 800 as a PWR S/G tube material  

International Nuclear Information System (INIS)

Resistance of Alloy 800 as a PWR S/G tube material to IGC/IGSCC and Ni, Co release into water was evaluated as compared with Alloys 600 and 690. The study to improve the resistance to IGSCC and general corrosion was also made, including the effects of shot-peening on the distribution of the residual stress of the U-bent tubes and the susceptibility to SCC, the stabilizing elements on IGC/IGSCC, and prior oxidation on general corrosion. From the results, shot-peened Alloy 800 was estimated to be the most reliable S/G tube material among the high nickel alloys tested. In addition, the Alloy 800 tube would obtain further reliability in IGSCC and general corrosion resistance by the combined addition of Ti, and Nb, and the prior oxidation of the inner tube surface, respectively.

1987-03-09

212

High-temperature low-cycle fatigue and tensile properties of Hastelloy X and alloy 617 in air and HTGR-helium  

Energy Technology Data Exchange (ETDEWEB)

Results of strain controlled fatigue and tensile tests are presented for two nickel base solution hardened alloys which are reference structural alloys for use in several high temperature gas cooled reactor concepts. These alloys, Hastelloy X Inconel 617, were tested at temperatures ranging from room temperature to 871/sup 0/C in air and impure helium. Materials were tested in the solution annealed as well as in the pre-aged condition where aging consisted of isothermal exposure at one of several temperatures for periods of up to 20,000 h. Comparisons are also given between the strain controlled fatigue lives of these alloys and several other commonly used alloys all tested at 538/sup 0/C.

1981-01-01

213

Forming characteristics of cast magnesium alloy sheets manufactured by roll strip casting process  

Energy Technology Data Exchange (ETDEWEB)

Plastic formability of cast magnesium alloy that were hot rolled after roll strip casting was investigated to ascertain the feasibility of semi-solid strip casting process of AZ31B magnesium alloy. Hot rolling and heat treatment conditions were changed to examine which conditions were appropriate for producing AZ31B wrought magnesium alloys after strip casting process. Microscopic observation of the crystals of the manufactured wrought magnesium alloys was performed. It has been found that a limiting drawing ratio of 2.7 was possible in a warm deep drawing test of the cast magnesium alloy sheets after being hot rolled. (orig.)

2004-07-01

214

Filler metal development for Hastelloy alloy XR. Filler metal for hastelloy alloy XR structure with thick wall  

Energy Technology Data Exchange (ETDEWEB)

In order to develop the filler metal for Hastelloy alloy XR structure with thick wall, the weldability and high temperature strength properties of Hastelloy alloy XR weldment were investigated using the filler metals, which were alloy-designed on the basis of multiple regression analysis. The former was examined through the chemical analysis in the deposited metal, bend test, FISCO cracking test, optical microscopy and hardness measurement. The latter was investigated by means of tensile and creep test. It was found from these results that the crack susceptibility in the weldment was apparent to be lowered without degrading the high temperature strength properties. Therefore, it is concluded that these filler metals possess excellent performance as the filler metal for Hastelloy alloy XR structure with thick wall. (author).

1991-11-01

215

Fabrication and characterization of Pd/Ag alloy hollow spheres by the solvothermal method  

Energy Technology Data Exchange (ETDEWEB)

Pd/Ag alloy hollow spheres have been synthesized in ethylene glycol solution by the solvothermal method and have been characterized extensively. TEM results have revealed the formation of Pd/Ag hollow spheres. Moreover, HRTEM results confirmed the formation of Pd/Ag alloy spheres, where the lattice fringe spacing is 0.229 nm corresponding to the (111) plane of Pd/Ag alloy. SEM, XRD and UV-vis results have further suggested the formation of alloy hollow spheres. The preliminary results showed the reaction time may be an importance factor influencing the formation of Pd/Ag alloy hollow spheres.

2008-03-15

216

Electrochemical behaviour of multicomponent Zr-Ti-V-Mn-Cr-Ni alloys in alkaline solution  

Energy Technology Data Exchange (ETDEWEB)

The effect of the composition of multicomponent Zr-Ti-V-Mn-Cr-Ni alloys on their hydrogen-storage capacity and on the rate of electrosorption/desorption hydrogen was investigated under potentiodynamics as well as single-pulse and long-term galvanostatic conditions. The main characteristics of alloys and alloy electrodes were determined by their structural analysis by means of X-ray diffraction and scanning electron microscope, by specific surface area test and by determination of the hydrogen absorption/desorption isotherms in the gas/solid phase system. It was found that only the alloys with a manganese content below a threshold could be used as electrode materials for Ni-MH batteries, whereas the modification of the electrode material by micro-encapsulation of alloy particles should limit the dissolution of manganese from the electrode material in a strong alkaline solution. ...

1996-01-01

217

Effects of rolling condition on warm deep drawability of magnesium alloy sheets produced by twin-roll strip casting  

Energy Technology Data Exchange (ETDEWEB)

Effects of rolling conditions on warm deep drawability of cast magnesium alloy that were hot rolled after roll strip casting were investigated to ascertain the feasibility of twin-roll strip casting process of AZ31B magnesium alloy. Hot rolling and heat treatment conditions were changed to examine which conditions were appropriate for producing AZ31B wrought magnesium alloys after strip casting process. Microscopic observation of the crystals of the manufactured wrought magnesium alloys was performed. It has been found that a limiting drawing ratio of 2.7 was possible in a warm deep drawing test of the cast magnesium alloy sheets after being hot rolled. (orig.)

2005-07-01

218

Development of plasticity processing of magnesium alloys  

Energy Technology Data Exchange (ETDEWEB)

Recent developments on plastic forming technology of magnesium alloys are presented. Attempts have been undergoing with an aim at forming magnesium alloy parts at lower temperatures. It is believed that fine microstructure magnesium alloys usually have much higher plasticity at lower temperatures and even room temperatures. Extrusion is a method to form magnesium profile products and tube products, which is also one of the effective ways to make fine microstructure magnesium alloys. Superplasticity forming is another method to form high plasticity magnesium alloys. Hot forming of magnesium sheet parts is an important process to form magnesium products. Some developments related to above issues are discussed in the present paper. (orig.)

2003-07-01

219

Corrosion resistance of tungsten and molybdenum alloys with #approx# 30 at.% Re in nitrogen- and oxygen-containing environments  

International Nuclear Information System (INIS)

Formation kinetics and composition of products of interaction of binary and ternary tungsten-molybdenum-rhenium alloys containing 30#+-#3 at.% (27-47 weight %) Re with products of thermal dissociation of ammonia and nitrogen-oxygeneous mixtures are studied. Mo-45% Re-10%W ternary alloy occupies intermediate position between W-27%Re and Mo-47%Re binary alloys, while its corrosion resistance and corrosion nature are close to those of W-Re and mechanical features - to those of Mo-Re alloy. It is explained by the fact, that the variation of W and Mo ration occurs in thin surface layer of ternary alloys in contrast to the initial state and the enrichment of near-the-surface layer with tungsten occurs under hot and cold deformation, at aging in the air, and during oxidation-reduction treatment. 4 refs.; 7 figs.

220

Corrosion behavior of sputter-deposited W-Nb alloys in NaCl and NaOH solutions  

International Nuclear Information System (INIS)

The corrosion behavior of the sputter-deposited amorphous or nanocrystalline W-Nb alloys is studied in 10% NaCl, 0.1 and 1 M NaOH solutions at 24 deg. C, open to air using immersion tests and electrochemical measurements. Niobium metal acts synergistically with tungsten in enhancing the corrosion resistance of the W-Nb alloys so as to show lower corrosion rates than the corrosion rates of the alloy-constituting elements in almost all examined solutions. Corrosion rates of W-Nb alloys are about more than one order of magnitude less than that of the sputter-deposited tungsten and even lower than that of sputter-deposited niobium. The stability of the anodic passive films formed on the W-Nb alloys increase with niobium content.

2008-05-29

221

Converting hcp Mg-Al-Zn alloy into bcc Mg-Li-Al-Zn alloy by electrolytic deposition and diffusion of reduced lithium atoms in a molten salt electrolyte LiCl-KCl  

Energy Technology Data Exchange (ETDEWEB)

A body-centered cubic (bcc) Mg-12Li-9Al-1Zn (wt.%) alloy was fabricated in air by electrolysis from LiCl-KCl molten salt at 500 deg. C. Electrolytic deposition of Li atoms on cathode (Mg-Al-Zn alloy) and diffusion of the Li atoms formed the bcc Mg-Li-Al-Zn alloy with 12 wt.% Li and only 0.264 wt.% K. Low K concentration in the bcc Mg alloy strip after the electrolysis process resulted from 47% atomic size misfit between K and Mg atoms and low solubility of K in Mg matrix.

2007-04-15

222

Converting hcp Mg-Al-Zn alloy into bcc Mg-Li-Al-Zn alloy by electrolytic deposition and diffusion of reduced lithium atoms in a molten salt electrolyte LiCl-KCl  

British Library Electronic Table of Contents (United Kingdom)

A body-centered cubic (bcc) Mg-12Li-9Al-1Zn (wt.%) alloy was fabricated in air by electrolysis from LiCl-KCl molten salt at 500degreeC. Electrolytic deposition of Li atoms on cathode (Mg-Al-Zn alloy) and diffusion of the Li atoms formed the bcc Mg-Li-Al-Zn alloy with 12wt.% Li and only 0.264wt.% K. Low K concentration in the bcc Mg alloy strip after the electrolysis process resulted from 47% atomic size misfit between K and Mg atoms and low solubility of K in Mg matrix.

2007-01-01

223

Caburization kinetics of alloy-800 in liquid sodium at 550_0C  

International Nuclear Information System (INIS)

Preliminary observations on the isothermal carbon transfer in low-carbon Alloy-800 exposed in sodium with AISI-304 type of steel at 550_0 are reported. The alloy was found to undergo a carburization comparable or slightly lower than that observed for the AISI-304 stainless steel for carbon activities above 6 x 10 /sup -3/ at 550_0C, but was not found to decarburize below such a carbon activity value. In the examined range the chemical composition of the alloys does not affect the process out of the experimental uncertainty of measure. Conclusions concerning the effective diffusion for carbon in the alloy are formulated. Preliminary relationships were found for an empirical evaluation of the carburization of the Alloy-800 in sodium of known carbon activity.

224

Anisotropy of the structure and mechanical properties of low-alloy tungsten  

Energy Technology Data Exchange (ETDEWEB)

The authors examine the relationship of the structure and mechanical properties of similar alloys of tungsten with rhenium produced by the powder metallurgy method by sintering powders. Since the alloys were deformed by rolling, we examine the effect of the resultant anisotropy of the structure on the properties of the metal in various directions. The tests were conducted on an alloy of tungsten with 2 wt.% rhenium and, for comparison purposes, an alloy of tungsten with additions of oxides of yttrium and hafnium. The mechanical properties of the alloys, i.e., strength, cracking resistance, cold shortness temperature, were determined in the bend test. Structural examination was carried out using an optical microscope, electron scanning microscopy, and the method of transmission electron microscopy.

1987-12-01

225

Advances in amorphous and nanocrystalline magnetic materials  

International Nuclear Information System (INIS)

Recent advances made in the area of amorphous and nanocrystalline alloys exhibiting high saturation inductions are reviewed. A new chemical composition was identified that achieves a saturation induction of 1.64 T in an iron-based amorphous alloy. This alloy, when used in electrical transformers, shows a much improved performance over the existing amorphous alloy. Nanocrystalline FeCoCuNbSiB alloys are found to have saturation induction levels reaching 1.7 T. These materials are suited for use in sensors and inductors carrying large currents. Some of these nanocrystalline alloys show a BH squareness ratio exceeding 90%, which can be utilized in pulse power devices. Recent developments in the applications of these materials are also pointed out.

2006-09-01

226

Present status of biological effects of toxic metals in the environment: lead, cadmium, and manganese  

Energy Technology Data Exchange (ETDEWEB)

The number of reports concerning the chemical toxicology of metals which are released in the environment by natural as well as anthropogenic sources, have been increasing constantly. Lead, cadmium, and manganese have found a variety of uses in industry, craft, and agriculture owing to their physical and chemical properties. The environmental burden of heavy metals has been rising substantially by smelter emission in air and waste sewage in water. Further, organic compounds of lead and manganese used as antiknock substances in gasoline are emitted into the atmosphere by automobile exhaustion. Such environmental contamination of air, water, soil, and food is a serious threat to all living kinds. Although these metals are known to produce their toxic effects on a variety of body systems, much emphasis has been placed on their effects on the nervous system owing to apparent association of relatively low or ''subclinical'' levels of ...

1984-08-01

227

Physical and electrochemical characterization of CdS hollow microspheres prepared by a novel template free solution phase method  

International Nuclear Information System (INIS)

Novel CdS hollow microspheres have been successfully synthesized via a facile template-free solution-phase reaction from cadmium nitrate and thioacetamide precursors. The morphology of CdS hollow microspheres depends strongly on the ratio between the precursors, cadmium nitrate to thioacetamide ratio. The physical properties of the hollow microspheres have systematically been studied by different characterization methods. The stoichiometry of the hollow microspheres studied by the energy dispersive X-ray diffraction spectroscopy confirmed that the synthesized CdS hollow microspheres are nearly stoichiometric bulk like CdS. The morphology of the hollow microspheres studied by high resolution scanning electron microscopy and transmission electron microscopy observations showed that the CdS hollow microspheres of the size of 2.5 ?m have hollow structure and are constructed by several nanoparticles of the size between 30 and 40 nm. The UV-visible ...

2010-12-15

228

Fatigue behavior of Alloy 690 and Alloy 800 SG tubing at temperatures up to 330{sup o}C in very high cycle fatigue regime  

Energy Technology Data Exchange (ETDEWEB)

During the service in nuclear power plants, steam generator (SG) tubing will suffer from a vibration with a frequency from 30-40 Hz. This means that SG tubing will undergo a very high cycle fatigue process during the design life time (25 years=about 3x10{sup 10}cycles). The material degradation and the very high cycle fatigue life of SG tubing materials due to the vibration are therefore of concern. In this investigation, the fatigue properties of Alloy 690 and Alloy 800 SG tubing in the very high cycle fatigue regime (higher than 10{sup 7} cycles) and strain controlled fatigue at temperatures up to 330{sup o}C have been investigated. The fatigue properties of SG tubing of Alloy 690 are comparable to that of wrought material. The strain controlled fatigue properties of Alloy 690 and Alloy 800 are slightly better at 288{sup o}C than at room temperature (RT). At the stress near the ...

2007-07-01

229

Fatigue behavior of Alloy 690 and Alloy 800 SG tubing at temperatures up to 330"oC in very high cycle fatigue regime  

International Nuclear Information System (INIS)

During the service in nuclear power plants, steam generator (SG) tubing will suffer from a vibration with a frequency from 30-40 Hz. This means that SG tubing will undergo a very high cycle fatigue process during the design life time (25 years=about 3x10"1"0cycles). The material degradation and the very high cycle fatigue life of SG tubing materials due to the vibration are therefore of concern. In this investigation, the fatigue properties of Alloy 690 and Alloy 800 SG tubing in the very high cycle fatigue regime (higher than 10"7 cycles) and strain controlled fatigue at temperatures up to 330"oC have been investigated. The fatigue properties of SG tubing of Alloy 690 are comparable to that of wrought material. The strain controlled fatigue properties of Alloy 690 and Alloy 800 are slightly better at 288"oC than at room temperature (RT). At the stress near the fatigue endurance, ...

2007-08-19

230

Reactor fuel cladding tube with excellent corrosion resistance and method of manufacturing the same  

International Nuclear Information System (INIS)

The present invention provides a fuel cladding tube having an excellent corrosion resistance and thus a long life, and a suitable manufacturing method therefor. Namely, in the fuel cladding tube, the outer circumference of an inner layer made of a zirconium base alloy is coated with an outer layer made of a metal more corrosion resistant than the zirconium base alloy. Ti or a titanium alloy is suitable for the corrosion resistant metal. In addition, the outer layer can be coated by a method such as vapor deposition or plating, not limited to joining of the inner layer material and the outer layer material. Specifically, a composite material having an inner layer made of a zirconium alloy coated by the outer material made of a titanium alloy is applied with hot fabrication at a temperature within a range of from 500 to 850degC and at a fabrication rate of not less than 5%. The ...

1993-07-14

231

Probabillistic Sensitivity Analysis in Life-Prediction of an alpha + beta Titanium Alloy.  

Science.gov (United States)

Probabilistic sensitivities using the score function method are developed for a lifing analysis of an alpha + beta titanium alloy in a round bar under axial fatigue load. Sensitivities with respect to the statistical inputs of the crack initiation size (a...

2008-01-01

232

On the possible relation between the absence of superconductivity in Au and Pd-Ag alloys and the negative sign of the Hall coefficient  

International Nuclear Information System (INIS)

Available data are presented which support the supposition that metals and alloys with a negative low-temperature Hall coefficient are apparently not superconducting. (author).

1983-01-01

233

Molar and excess volumes of liquid In-Sb, Mg-Sb, and Pb-Sb alloys  

Energy Technology Data Exchange (ETDEWEB)

By a direct Archimedes' technique, volumetric data were obtained for liquid In, Mg, Pb, and Sb and mixtures of In-Sb, Mg-Sb, and Pb-Sb. In this paper the excess volumes for the alloys studied are presented and discussed.

1990-04-01

234

Improvement of structure and mechanical properties of cast titanium alloys using rapid heat treatment  

Energy Technology Data Exchange (ETDEWEB)

The possibility of rapid heat treatment (RHT) application to titanium castings has been studied. It was shown that such treatment provides a significant improvement of intragrain structure and mechanical properties of cast ({alpha}+{beta})-titanium alloys. ((orig.))

1995-01-01

235

High damping Fe-Mn martensitic alloys for engineering applications  

International Nuclear Information System (INIS)

Conventional methods for reducing vibration in engineering designs (i.e. by stiffening or detuning) may be undesirable or inadequate in conditions where size or weight must be minimized or where complex vibration spectra exist. Alloys which combine high damping capacity with good mechanical properties can provide attractive technical and economic solutions to problems involving seismic, shock and vibration isolation. To meet these trends, we have developed a new high damping Fe-17%Mn alloy. Also, the alloy has advantages of good mechanical properties and is more economical than any other known damping alloys (a quarter the cost of non-ferrous damping alloy). Thus, the high damping Fe-17%Mn alloy can be widely applied to household appliances, automobiles, industrial facilities and power plant components with its excellent damping capacity (SDC, 30%) and ...

2000-06-01

236

Electrolysis of halide-containing solutions with platinum based amorphous metal alloy anodes  

Energy Technology Data Exchange (ETDEWEB)

A process for the generation of halogens from halide-containing solutions includes the step of conducting electrolysis of the solutions in an electrolytic cell having a platinum based amorphous metal alloy anode.

1985-12-24

237

Electrochemical properties of Si/Ni alloy-graphite composite as an anode material for Li-ion batteries  

International Nuclear Information System (INIS)

Si/Ni alloy and graphite composites were synthesized using arc-melting followed by high energy mechanical milling (HEMM). Alloy particles comprising of NiSi2, NiSi and Si phases were distributed finely and uniformly on the surface of graphite in the composites obtained after Hem. The composite containing 60 wt.% of Si/Ni alloy exhibited a stable capacity of ?780 mAh/g. Fourier transform infrared spectroscopy (FTIR) analysis confirmed that some bonds were formed between alloy and graphite after HEMM, which appeared to retain the electrical connection between alloy and graphite during cycling. X-ray diffraction (XRD) analysis indicated that NiSi2 and NiSi phases, which acted as an inactive alloy matrix remained invariant during charge and discharge. In addition to NiSi2 and NiSi phases, disordered graphite layers also played the role of media for the accommodation ...

2005-09-30

238

Electrochemical corrosion behavior of AZ91D alloy in ethylene glycol  

Energy Technology Data Exchange (ETDEWEB)

The effect of concentration on the corrosion behavior of Mg-based alloy AZ91D was investigated in ethylene glycol-water solutions using electrochemical techniques i.e. potentiodynamic polarization, electrochemical impedance measurements (EIS) and surface examination via scanning electron microscope (SEM) technique. This can provide a basis for developing new coolants for magnesium alloy engine blocks. Corrosion behavior of AZ91D alloy by coolant is important in the automotive industry. It was found that the corrosion rate of AZ91D alloy decreased with increasing concentration of ethylene glycol. For AZ91D alloy in chloride >0.05 M or fluoride <0.05 M containing 30% ethylene glycol solution, they are more corrosive than the blank (30% ethylene glycol-70% water). However, at concentrations <0.05 for chloride or >0.05 M for fluoride containing ethylene ...

2009-11-01

239

Electrochemical corrosion behavior of AZ91D alloy in ethylene glycol  

International Nuclear Information System (INIS)

The effect of concentration on the corrosion behavior of Mg-based alloy AZ91D was investigated in ethylene glycol-water solutions using electrochemical techniques i.e. potentiodynamic polarization, electrochemical impedance measurements (EIS) and surface examination via scanning electron microscope (SEM) technique. This can provide a basis for developing new coolants for magnesium alloy engine blocks. Corrosion behavior of AZ91D alloy by coolant is important in the automotive industry. It was found that the corrosion rate of AZ91D alloy decreased with increasing concentration of ethylene glycol. For AZ91D alloy in chloride >0.05 M or fluoride 0.05 M for fluoride containing ethylene glycol solution, some inhibition effect has been observed. The corrosion of AZ91D alloy in the blank can be effectively inhibited by addition of 0.05 mM paracetamol that reacts ...

2009-11-01

240

Development of modified 9 Cr-1 Mo steel for elevated-temperature service  

International Nuclear Information System (INIS)

The status of development and commercialization of a modified 9 Cr-1 Mo alloy is presented. The alloy is modified by the addition of 0.06 to 0.10% Nb and 0.18 to 0.25% V. The alloy is recommended for use in the normalized and tempered condition (1040"0C for 1 h, air cooled to room temperature; 760"0C for 1 h, air cooled to room temperature). Heat treatment, Charpy impact, tensile, and creep properties of the alloy are described in detail along with a brief description of other properties. The modified alloy has creep strength that exceeds that of standard 9 Cr-1 Mo and 2 1/4 Cr-1 Mo steels for the temperature range from 427 to 704"0C. The total-elongation and reduction-of-area values for all test temperatures and rupture times up to 22,500 h exceed 15 and 70%, respectively. The estimated design allowable stresses for this alloy are higher than those for standard ...

1983-06-19

241

Correlation of mechanical properties with microstructure of Alloy 800 after annealing at 800 - 1000 "0C  

International Nuclear Information System (INIS)

The microstructures of so called high temperature alloys, which have been developed for service temperatures up to 800"0C, are not necessarily stable at higher temperatures. The mobility of alloying elements is very high in FeCrNi alloys at 950 "0C e.g. iron, chromium or nickel can diffuse up to 0.1 mm distance in one year, which is about a grain diameter. Interstitials like carbon or nitrogen show a four orders of magnitude higher diffusivity than the alloying elements. In addition, the carbon solubility in this type of alloy is reported to be very low. Therefore the alloys are supersaturated with carbon after heat treatment above 1100 "0C and water quenching although the absolute carbon content is very low. At service temperatures around 800"0C the solubility of carbon is still about one order of magnitude lower than at heat treatment temperature. This will ...

1981-05-01

242

Comparison of Optical and SEM BSE Imaging Techniques for Quantifying Alpha-Beta Titanium Alloy Microstructures (Preprint).  

Science.gov (United States)

Quantitative metallography is often used to confirm the proper processing of aerospace metallic materials. A microstructural feature of great importance for titanium alloys processed in the alpha-beta phase field is the volume fraction of primary alpha. S...

2006-01-01

243

Carburization and tensile behavior of alloy 800 in liquid sodium  

International Nuclear Information System (INIS)

The carbon transfer has been analyzed in the Alloy 800/sodium/stainless steel system by determining the carbon-uptake of Alloy 800 foils, which were exposed in liquid sodium of known carburizing potential. Under equilibrium condistions between 650 and 550_0C the measured total carbon concentrations in the Alloy 800 tabs were found to be roughly related to the carbon activities of the sodium environment by the equation already stated for the 18 Cr-8/10 Ni stainless steels, extrapolated to the chemical composition of the Ni-rich austenitic alloy. However the Alloy 800 was not found to undergo any decarburization in low-carbon activity environments. The carbon diffusion kinetics was determined as a function of temperature, it was found to be similar to that reported for the AISI-304 type of steel. The effects of sodium exposure on microstructural and mechanical properties of several ...

244

Carburization and tensile behavior of Alloy 800 in liquid sodium  

Energy Technology Data Exchange (ETDEWEB)

The carbon transfer has been analyzed in the Alloy 800/sodium/stainless steel system by determining the carbon-uptake of Alloy 800 foils, which were exposed in liquid sodium of known carburizing potential. Under equilibrium conditions between 650 and 550/sup 0/C the measured total carbon concentrations in the Alloy 800 tabs were found to be roughly related to the carbon activities of the sodium environment by the equation already stated for the 18 Cr-8/10 Ni stainless steels, extrapolated to the chemical composition of the Ni-rich austenitic alloy. However the Alloy 800 was not found to undergo any decarburization in low-carbon activity environments. The carbon diffusion kinetics was determined as a function of temperature, it was found to be similar to that reported for the AISI-304 type of steel. The effects of sodium exposure on microstructural and mechanical properties of ...

1983-05-01

245

Absorption and diffusion of hydrogen in palladium-silver alloys by density functional theory  

Science.gov (United States)

The vibrational states, absorption energies, and diffusions of H in Pd and Pd1-xAgx(0Pd-Ag alloys should avoid the Ag-rich areas.

2002-11-01

246

Wettability of binary and ternary alloys of the system Al-Si-Mg with SiC particulates  

Science.gov (United States)

The authors have presented results of an investigation of wettability of SiC particulates by liquid alloys of the Al-Si-Mg system. The evaluation of wetting has been carried out through the determination of the threshold pressure for infiltration of packed SiC particulates by the liquid alloy. The results indicate that whereas Si and Mg additions do not affect wetting, in the case of the ternary alloys the contact angle decreases in an amount proportional to the content of Mg[sub 2]Si.

1994-12-01

247

Wear and friction measurements on CVD coated carbon alloy bearing surfaces  

Energy Technology Data Exchange (ETDEWEB)

A series of ball-on-disc wear and friction measurements were made for surfaces which have a chemical vapour deposition carbon silicon alloy layer on a carbon substrate (fine grain POCO graphite). Nitrogen ion irradiation was used to improve the wear resistance of the carbon alloy surface. For comparison, measurements were also taken for alumina against alumina. It was found that the lowest friction coefficient and lowest wear occurred for ion irradiated coated samples containing 4% Si in the alloy and that the performance was superior to that of alumina. ((orig.))

1995-03-01

248

Wear and friction measurements on CVD coated carbon alloy bearing surfaces  

International Nuclear Information System (INIS)

A series of ball-on-disc wear and friction measurements were made for surfaces which have a chemical vapour deposition carbon silicon alloy layer on a carbon substrate (fine grain POCO graphite). Nitrogen ion irradiation was used to improve the wear resistance of the carbon alloy surface. For comparison, measurements were also taken for alumina against alumina. It was found that the lowest friction coefficient and lowest wear occurred for ion irradiated coated samples containing 4% Si in the alloy and that the performance was superior to that of alumina. ((orig.)).

249

Total corrosion and film analysis of SUS and Ni base alloy in supercritical water  

International Nuclear Information System (INIS)

... Toshiba Corporation, Isogo Engineering Center, Yokohama, Kanagawa (Japan)

2005-09-01

250

The effects of high-temperature exposure on the properties of heat-resistant alloys  

Energy Technology Data Exchange (ETDEWEB)

The exposure of heat-resistant alloys to high temperature can significantly change their mechanical properties. This paper presents and analyzes data on the effect of thermal exposure on the tensile and impact behavior of three cast materials -- the HK-40, HP-50, and 21Cr-32Ni-Fe alloys -- and of wrought material -- Alloy 800. The changes in tensile and impact properties caused by high-temperature exposure are reviewed. Reasons for these property changes and needs for considering them in the design, operation, and life assessment of high-temperature equipment are discussed.

1994-12-31

252

Study of the natural and passive oxide films formed on Ni-Mo single crystal alloys by ion channelling and nuclear microanalysis  

Energy Technology Data Exchange (ETDEWEB)

The chemical properties of alloys in a given environment are to a large extent governed by the surface composition. Changes of the surface composition during passivation are important features in this respect. Previous studies of single crystal Ni-Mo alloys surfaces have been reported. The aim of this work was to obtain quantitative data, for the natural oxide and the passive films formed on Ni-6% Mo(100) and (110) alloys, using Rutherford backscattering spectroscopy and nuclear reaction analysis.

1988-07-01

253

Study of the natural and passive oxide films formed on Ni-Mo single crystal alloys by ion channelling and nuclear microanalysis  

International Nuclear Information System (INIS)

The chemical properties of alloys in a given environment are to a large extent governed by the surface composition. Changes of the surface composition during passivation are important features in this respect. Previous studies of single crystal Ni-Mo alloys surfaces have been reported. The aim of this work was to obtain quantitative data, for the natural oxide and the passive films formed on Ni-6% Mo(100) and (110) alloys, using Rutherford backscattering spectroscopy and nuclear reaction analysis. (author).

1987-10-19

254

Structural transformations of metastable #alpha#''-phase during cold deformation  

International Nuclear Information System (INIS)

Phase transformations occuring during cold deformation in hardened #alpha#+#beta# titanium alloy of the Ti-Al-Mo-Zr-Sn-Si system with 10% summary content of alloying elements are studied by X-ray diffraction analysis. Two stages of trapsformation of metastable #alpha#''-phase are found. A conclusiop is made that ability of the alloy containing #alpha#''-phase to cold deformation is determined by the presence of favourable texture, by high degree of metastability and by volume portion of #alpha#''-phase in the alloy structure.

255

Raising the durability of bucket wheel excavator teeth  

Energy Technology Data Exchange (ETDEWEB)

Describes performance of excavator teeth manufactured with a new hard alloy. The alloy was developed by the Donetskii Politeknicheskii Institute. Its composition consists of a high-chromium steel with a larger amount of titanium than serial alloy, and a nitrogen additive. Trial tests of new alloy teeth were carried out in the Severnyi and Vershinskii coal surface mines. The teeth were attached to EhRP, EhPG and EhR bucket wheel excavators. Abrasive wear of 129 experimental teeth and 134 serial teeth was compared for different excavation conditions. Test results are tabulated; advantages of the new experimental teeth are listed. 3 refs.

1993-07-01

256

Pitting corrosion of nickel base alloys in halide media  

International Nuclear Information System (INIS)

A computerized corrosion measuring system (EG and G model 350 A) was used to study the influence of Cr, Mo, Ti, Nb and W on the pitting corrosion of nickel base alloys in 3% NaCl at 90"0C. The electrochemical parameters under investigation are the corrosion potential E_c_o_r_r, pitting potential E_p and protection potential E_p_p. The corrosion behaviour of nickel base alloys were studied by using pitting scan and potentiostatic techniques. Values of corrosion potential, pitting potential and protection potential were used for a ranking of alloys for corrosion resistance.

1988-03-06

257

Operating experience with condenser tubes made from copper alloys and new developments; Betriebserfahrungen mit Kondensatorrohren aus Kupferlegierungen und aktuelle Entwicklungen  

Energy Technology Data Exchange (ETDEWEB)

Copper alloys are a suitable tubing material for turbine condensers and heat exchangers. Due to problems with corrosions copper alloys increasingly are displaced by high-grade steel and titanium. Blockages and surface formation in the pipes, disturbance of the oxide coating formation, erosion and quality faults with the production are the causes for the corrosion. In the contribution under consideration counter measures are designated for the solution of the problems with corrosions. The application limits for different copper alloys are designated. Recommendations for the optimized operation are given.

2008-07-01

258

Nanocrystallization of the amorphous Fe_1_4Ni_4_0Zr_7B_1_2 alloys studied by the Moessbauer spectroscopy  

International Nuclear Information System (INIS)

Formation of the soft magnetic nanostructure in amorphous Fe_1_4Ni_4_0Zr_7B_1_2 alloy due to heat treatment is studied by the Moessbauer, differential scanning calorimetry, and X-ray diffraction techniques. Annealing at temperatures 520-580 "oC leads to the formation of extremely soft nanocrystalline alloy as revealed by the rf-Moessbauer measurements. The superparamagnetic behaviour was observed for the alloy annealed at 620-640 "oC. At higher annealing temperatures good soft magnetic properties deteriorate. (author)

2001-09-23

260

Examination of electrochemical behavior and structure of oxide films on Ni/sub 60/Nb/sub 40/ alloy in amorphous and crystalline states  

Energy Technology Data Exchange (ETDEWEB)

Experiments were conducted which established that the higher passivating capacity of Ni/sub 60/Nb/sub 40/ alloys in the amorphous state and higher efficiency of the anodic process of generation of chlorine (2 N NaCl + HCl to pH = 0) in comparison with the crystalline state are determined by higher homogeneity and density of the passive films formed on the amorphous alloy and by higher electron conduction which depends directly on the difference in the structure of the passive films formed on the alloys in the amorphous and crystalline states.

1988-05-01

261

Environmental Influence on Passive Films Formed on Alloy 22  

Energy Technology Data Exchange (ETDEWEB)

The passive corrosion rate of Alloy 22 is exceptionally low in a wide range of aqueous solutions, temperatures and electrochemical potentials, Alloy 22 contains approximately 22% chromium (Cr) by weight; thus, it forms a Cr-rich passive film in most environments. Very little is known about the composition, thickness and other properties of this passive film. The aim of this research was to determine the general characteristics of the oxide film that forms on Alloy 22, as a function of solution pH, temperature and applied electrochemical potential.

2002-10-07

262

Electron microscopy study of thermomechnical deformation conditions effect on the structure of two-phase (#alpha#+#beta#) titanium alloys  

International Nuclear Information System (INIS)

The methods of optical and transmission electron microscopy were used to study the influence of different programmes of hot deformation on the structure formation of (#alpha#+#beta#) titanium alloy VT9. The #beta# alloy VT-15 was studied at the same time in order to simulate the dislocation structure generated in the process of hot deformation. During the hot deformation of two-phase titanium alloys in both #beta# and (#alpha#+#beta#) ranges there is found to be an optimum range of deformation in which a homogeneous, polygonized structure is formed.

263

Electrochemical behavior of Alloy 800 under steam generators temperature and pressure conditions comparison, based on (I,E) polarization curves, with 316L and A533B steels  

Energy Technology Data Exchange (ETDEWEB)

We propose a dissolution-passivation model to account for the electrochemical behavior of Alloy 800 and 316L stainless steel under steam generators operating conditions. This model is similar to the one defined for nickel, considering the known importance of this element on the studied alloys. The comparison of the rates of the elementary steps points out the favorable influence of dissolved oxygen and phosphate ions on the dissolution of Alloy 800, even in the presence of chloride ions. The sensitivity of 316L SS is greater, especially because of the lowest stability of oxide-like intermediate.

1992-12-31

264

Electrochemical behavior of Alloy 800 under steam generators temperature and pressure conditions comparison, based on (I,E) polarization curves, with 316L and A533B steels  

International Nuclear Information System (INIS)

We propose a dissolution-passivation model to account for the electrochemical behavior of Alloy 800 and 316L stainless steel under steam generators operating conditions. This model is similar to the one defined for nickel, considering the known importance of this element on the studied alloys. The comparison of the rates of the elementary steps points out the favorable influence of dissolved oxygen and phosphate ions on the dissolution of Alloy 800, even in the presence of chloride ions. The sensitivity of 316L SS is greater, especially because of the lowest stability of oxide-like intermediate.

1991-08-25

266

Effect of tritium and helium-3 on the lifetime properties of Pd-Ag alloys in ITER tritium purification technology  

Energy Technology Data Exchange (ETDEWEB)

An experimental verification for long-term performance of a Pd-Ag permeation in ITER tritium fusion cleanup units (FCU) is needed. In addition, information is required on the influence of tritium and {sup 3}He decay on the physical and chemical properties of Pd-Ag alloys (V-1). The results of the investigations of alloys (V-1) (mechanical properties and microstructure) after long-term usage exposition in tritium are given in this report. The experimental conditions (temperature, pressure, clearance, {sup 3}He concentrations) and the previous conclusions on the V-1 alloy performance are presented. (orig.).

1996-10-01

267

Effect of protective coatings on the high-temperature fatigue of heat-resistant alloys  

Energy Technology Data Exchange (ETDEWEB)

The fatigue properties of EP539LM alloy with an Al-Nb-Si fused slurry coating and a Co-Cr-Al-Y electron-beam coating are investigated experimentally in vacuum and in air at 900 C. It is found that the protective coatings reduce the fatigue life of the specimens both in vacuum and in air, with the electron-beam coating affecting the fatigue life of the alloy to a lesser degree than the fused slurry coating. The negative effect of the coatings on the fatigue life of the alloy is attributed largely to the properties of the coating material. 7 references.

1986-08-01

268

Effect of cross rolling parameters on texture formation and parameters on texture formation and anisotropy of mechanical properties of (#alpha#+#beta#)-titanium alloy sheets  

International Nuclear Information System (INIS)

Formation of basis type texture at rolling of Ti + 6.0% Al + 1.5% V + 1.0% Mo system alloy with initial prismatic texture is investigated by means of X-ray techniques. Variations of mechanical features in titanium alloy sheets depending on temperature-deformation conditions of rolling are investigated. Main conditions for formation of the intensive basis textute in the investigated alloy sheets which provides for isotropic properties in sheet plane and for increased ductility are determined.

269

DEFORMATION BEHAVIOR OF AN OMEGA HARDENED ...  

Science.gov (United States)

... Accession Number : ADD100229. Title : DEFORMATION BEHAVIOR OF AN OMEGA HARDENED ALPHA-BETA TITANIUM ALLOY,. ...

270

Corrosion behaviour of non-ferrous metals in sea water  

Energy Technology Data Exchange (ETDEWEB)

The most typical kinds of corrosion of brasses are selective corrosion (dezincification) and stress corrosion. Prevention against these kinds of corrosion lies in application of arsenic alloy addition and appropriate heat treatment removing internal stresses as well as in maintaining the arsenic and phosphorus contents on a proper level. The most typical corrosion of cupronickels is the local corrosion. Selective corrosion occurs less often and corrosion cracking caused by stress corrosion in sea water does not usually occur. Crevice corrosion is found especially in places of an heterogeneous oxidation of the surface under inorganic deposits or under bio-film. Common corrosive phenomena for brasses and cupronickels are the effects caused by sea water flow and most often the impingement attack. Alloy additions improve resistance to the action of intensive sea water flow but situation in this field requires further improvement, especially if the ...

2004-07-01

271

Characteristics of the Mechanical Properties and the Fractures ...  

Science.gov (United States)

... Accession Number : ADA136144. Title : Characteristics of the Mechanical Properties and the Fractures of an Alpha Beta Titanium Alloy,. ...

1983-11-18

272

BNES materials conference a status review of alloy 800  

International Nuclear Information System (INIS)

Existing applications of Alloy 800 are summarized, with particular reference to its use in various types of reactor. The need for a co-ordinated research and development programme is stressed, and the variables to be explored are outlined. The papers relating to the problem of corrosion and cracking in water and steam are considered. the strength and ductility of Alloy 800 is considered. Finally, sections of the summary deal with the use of Alloy 800 for (a) sodium cooled fast reactor boiler tubes; (b) the high temperature gas cooled reactor; and (c) PWR steam generator tubes. (U.K.).

273

Application properties of AB{sub 2}-type hydrogen absorbing alloys  

Energy Technology Data Exchange (ETDEWEB)

Use of hydrogen absorbing alloys in various practical applications is always connected with the problem of production of starting alloys. The transition from laboratory samples to small-scale production involves the change of furnace and its operation mode and this has an effect on the preparation method of mixture of starting metal. Also, for some applications such as thermosorption compressors the exact values of thermodynamical parameters of reaction are needed. In the present work we present the results of investigation of series Laves phase hydrogen-absorbing alloys which can be promising in for use in different devices. 1 ref.

1998-07-01

274

The influence of process parameters on forged magnesium alloys  

Energy Technology Data Exchange (ETDEWEB)

Two extruded magnesium alloys, AZ31 and AZ61 were selected to evaluate the influence of process parameters on the material forgeability. The processing parameters considered for forging magnesium alloys were: compression load in the range 55 KN to 60 KN and forging temperature, in the range of ambient temperature to 300 C. Uniaxial compression tests were conducted to establish the strain-temperature relationship. The influences of process parameters on the microstructure were also evaluated. (orig.)

2003-07-01

275

Structural features of twins in transition class alloy Ti-Al-Mo-V-Cr  

International Nuclear Information System (INIS)

The alloy of Ti-Al-Mo-V-Cr system is studied for its structure in a strained state and specific features of #beta#-#alpha# transformation in a #beta#-matrix and deformation twins on ageing. It is determined that preliminary deformation initiates the decomposition of solid solution on aging. In a metastable #beta#-titanium alloy the substructure of deformation twins is shown to vary essentially with aluminium and chromium partial substitution for molybdenum and vanadium

1999-11-01

276

Strontium as modifier for AlSi and AlSiCu alloys  

International Nuclear Information System (INIS)

The optimum of strontium amount for good modification of AK7, AK9, AK11, AK52, AK104 alloys was determined on the base of the analysis of microstructural changes. The stability of the modifier was investigated on the way of successive remelting of billets. The influence of amount of modifier on the impact strength of the alloys was established. (author)

277

Mechanical properties of (alpha+beta)-titanium alloys with various structure within the temperature range of 20 to -196 deg C  

International Nuclear Information System (INIS)

The influence of structure on mechanical properties in the course of tensile tests in a wide range of temperatures was studied, using the VT16 structure thermally strengthened (alpha+beta)-titanium alloy by way of example. It is ascertained that transition from ductile to brittle fracture at the temperature of -196 deg C is observed only in coarse-grain alloy having alpha-eldging of beta grains.

278

Magnesium foam produced from bulk AZ31 magnesium alloy sheets  

Energy Technology Data Exchange (ETDEWEB)

Using commercial AZ31 magnesium alloy sheets, we produced a foamable preform sheet containing titanium hydride (TiH{sub 2}) powder through diffusion-bonding and hot-rolling of four cycles. Heating the preform sheets in Ar atmosphere, we obtained closed-cell magnesium alloy foams with various porosities. The foamed specimen at 883 K showed the maximum porosities of 77%. (orig.)

2005-07-01

279

Low temperature superplasticity of a metastable #beta#-titanium alloy  

International Nuclear Information System (INIS)

Superplasticity in Ti alloys has been widely investigated in the past and superplastic forming of aerospace components has thus been developed over the last two decades. The Ti alloy most studied in this framework is undoubtedly the Ti-6Al-4V (wt %) alloy, for which maximum elongations are obtained in the temperature range [880-900C]. The development of the superplastic properties has been demonstrated to be in close relation with quite similar volume fractions of the #alpha# and #beta# phases, the #beta# transus temperature for this alloy ranging from 980-1000 C. Attempts have been carried out to reduce the temperature of superplastic forming of Ti-6Al-4V by the addition of elements like Fe, Co, or Ni. Such an introduction of alloying elements indeed results in a decrease of the optimum forming temperature to values as low as 820 C. This decrease is mainly attributed to a change in ...

280

Implantation-plasma treatment of martensitic steel and titanium alloy  

Energy Technology Data Exchange (ETDEWEB)

One of the effective methods of deep modification of the surface of steels and alloys is the combination of ion implantation and plasma nitriding. In this work, the long-range effect is demonstrated in the case of combination of the effect of high- and low-energy ions of nitrogen on a martensitic steel for each ion implantation is usually not effective, and a titanium alloy used widely in industry.

2001-07-01

281

Grain boundaries structure and mechanical properties of aluminium alloys  

Energy Technology Data Exchange (ETDEWEB)

The paper discusses the problem of influence of grain boundaries structure on mechanical properties of aluminium alloys at elevated temperatures. Showed the data amount of grain boundaries close to special and a random of grain boundaries. The results of calculation of contribution of different mechanisms of deformation to the total deformation for alloys with different types of grain boundaries are given. (orig.)

1996-08-01

282

Formation of interphase layers in titanium alloys under repeated loading  

International Nuclear Information System (INIS)

Cyclic strength of #alpha#+#beta#-titanium alloy BT3-1 is studied under load frequencies of 33 and 300 Hz. The increase in the cyclic strength with growing frequency is caused by formation of FCC interphase layers of titanium hydrides. Their formation is one of possible ways of raising the fatigue strength of titanium alloys. Peculiarities of FCC interlayer formation in #alpha#+#beta# phases under loading frequency variation are revealed.

283

Effect of cooling conditions during heat treatment on mechanical properties of titanium alloy VT3-1  

International Nuclear Information System (INIS)

Effect of cooling rates within the wide range (0.003-45 grad/s) on the complex of mechanical properties of (#alpha#-#beta#)-titanium alloy VT3-1 is studied in the process of heat treatment. Cooling conditions of semifinished product made of this alloy with a different structure providing optimum combination of strength, ductility fracture toughness, heat resistance, and endurance are determined.

284

Development of lead-free copper alloy graphite castings. Annual report, January--December 1995  

Energy Technology Data Exchange (ETDEWEB)

The distribution of graphite particles in graphite containing copper alloy was further improved very significantly using several procedures and technological modifications. The developed techniques attacked the graphite distribution problem in two ways. Realizing that clustering of very fine (5um) graphite particles is one of the two major problems, a pretreatment process has been developed using aluminum powders to deagglomerate graphite particles. Along with this, a two-stage stirring technique was used to first incorporate and then to distribute uniformly the deagglomerated particles in the melt. During this year, based on these developments, several components were cast to evaluate the castability of Cu alloy-graphite melts. In addition, machinability tests were done to clearly established that addition of graphite particles improve the machinability of copper MMC alloys over and above that of monolithic copper ...

1996-10-01

285

Deep drawing and impact extrusion of magnesium alloys at room temperature  

Energy Technology Data Exchange (ETDEWEB)

Magnesium alloys and composites are potentially highly attractive materials for lightweight design in the automotive industry - if common forming technologies, i.e., deep drawing and cold extrusion, are applicable to them; so far, this is seldom the case. The authors have tested some candidate Mg alloys and discuss the results of their measurements in detail. The Figure shows a typical workpiece part obtained by a deep-drawing technique. (Abstract Copyright [2003], Wiley Periodicals, Inc.)

2003-04-01

286

Decomposition of metastable solid solution in #beta#-titanium alloy  

International Nuclear Information System (INIS)

Peculiarities of metastable #beta#-solid solution decmposition in titanium alloy VT30 in the process of isothermal ageing in the range 500-650 deg C are investigated. Using the methods of transmittion electron microscopy, X-ray diffraction analysis, etc., it is shown that in the case of alloy quenching from the temperature below the point of complete polymorphous transformation (T_t_._t_.), as well as after warm rolling the course of subsequent decomposition of solid solution can be consierably complicated.

287

Corrosion resistance of metals in hot hydroxide solutions  

International Nuclear Information System (INIS)

Effect of hydroxide nature, concentration and temperature on corrosion resistance of domestic steels and alloys to hot NaOH, KOH, LiOH solutions is considered. It is ascertained that by corrosion growth in relation to stainless steels and nickel alloys, the hydroxides are placed in the following sequence: LiOHalloy tendency to cracking is manifested, are determined. 12 refs., 12 figs.

288

Corrosion in power plant condensers  

International Nuclear Information System (INIS)

A historical overview of corrosion problems found in power plant condensers and mitigation procedures is presented. The paper is organized according to alloy type and failure mode. Alloys considered are copper-base alloys, stainless steels and titanium. Failure modes discussed include erosion-corrosion, sulfide attack, environmentally assisted cracking, galvanic corrosion, steam condensate corrosion, pitting corrosion, and dealloying. Mitigation procedures discussed include cathodic protection, ferrous ion injection, as well as tube cleaning and layup practices.

289

Calculation method of elastic moduli of textured two-phase titanium alloys  

International Nuclear Information System (INIS)

On the basis of symmetry way of texture description a calculation method of elastic moduli of two-phase titanium alloys with rolling texture has been suggested. Efficiency of the calculation formulas is checked by comparing the calculation results of Young modulus anisotropy in the sheet plane of (#alpha#+#beta#)-titanium alloy VT23 with the experimental data.

290

Vacuum distillation refining and recycling of magnesium alloys  

Energy Technology Data Exchange (ETDEWEB)

Purification parameters of the vacuum distillation process for AM50A and AZ31B magnesium alloy were studied. The vacuum distillation tests were kept at 580 C to 620 C up to 10 h under a vacuum pressure of about 1 Pa. The purification ratio for AM50A magnesium alloy increases with increasing the purification time. The chemical compositions of materials deposited purifying at 580 C for AM50A magnesium alloy almost satisfy the values for pure magnesium specified by JIS standard specification. The chemical compositions of deposited materials at 600 C for AZ31B magnesium alloy satisfy the values specified by the standard specification except for Zn. (orig.)

2003-07-01

291

TEM analyses of heterogeneous nucleation of internally oxidised multi-component Ag-Zn-based alloys  

Energy Technology Data Exchange (ETDEWEB)

The aim of our research was to identify structures and chemical compositions of phases formed during internal oxidation of multi-component Ag-Zn-Mg-based alloys. Since the ability of inoculation mostly depends on large free energy of formation of oxides of microalloying elements and their crystallographic similarity, Mg in quantities of 0.001-0.5 mass% was selected as a micro-alloying element. These correspond to the quantities of 0.005-2.5 vol.% of MgO in the selected Ag-Zn-based alloys. Ag-based metal matrix, heterogeneous nuclei of MgO and oxide (ZnO) of the main alloying element were analysed by transmission electron microscopy (TEM). Structural inter-connections among them were also investigated and analysed. In situ phenomenon of heterogeneous nucleation of MgO and ZnO was proved. (orig.)

2001-11-01

292

Structure transformation and gain in properties of cast high-temperature T-6242 alloy by thermo-hydrogen treatment  

International Nuclear Information System (INIS)

Thermohydrogen treatment effect on microstructure and mechanical properties is studied for a cast heat resistant pseudo-#alpha#-titanium alloy Ti-6242 (Ti-6Al-2Sn-4Zn-2Mo) widely used as a heat resistant material with operating temperature up to 500 deg C. It is shown that reversible hydrogen alloying is a promising alternative to thermomechanical treatment for transformation of (#alpha#+#beta#)-titanium alloy structure. The application of thermohydrogen treatment is noted to be of particular efficiency for shaped casting technology as it allows a noticeable increase of mechanical properties at a lower cost. The alloy after thermohydrogen treatment and subsequent heat treatment in the (#alpha#+#beta#) - range possesses high values of yield strength fatigue properties, creep resistance and has a satisfactory ductility. A consideration is also given to thermohydrogen treatment effect on fatigue crack ...

293

Structure and properties of a metastable #beta#-alloy aged after plastic deformation  

International Nuclear Information System (INIS)

Phase and structural transformations in a multicomponent (5.05 mas.% Mo-4.95V-3.00Cr-3.05Al) metastable #beta#-titanium alloy on aging after plastic deformation are studied using methods of electron microscopy and X-ray diffraction analysis. The alloy is deformed by twinning in a #left brace#332#right brace# system, and even at initial stages the formation of a twin skeleton takes place in the structure, on further loading the deformation of the skeleton is by secondary twinning resulting in a high plasticity of the alloy. On annealing mechanical twins transform into #alpha#-phase - a ductile twin skeleton is replaced by a rigid skeleton of #alpha#-phase plates. The aging enhances the yield strength of the alloy but decreases sharply its plasticity

2004-12-01

294

Stress-induced martensitic transformation of metastable #beta#-titanium alloy  

International Nuclear Information System (INIS)

The constituent phases and associated deformed microstructure of the quenched Ti-xNb-(0.5-1.5) at.% Si alloy consisting of non-cytotoxicity elements, where x = 24-30 at.%, were investigated to provide pseudoelasticity for biomedical and sensor applications. Optical microscopy revealed that stress-induced martensitic transformation takes place during the deformation in the present alloys. It is confirmed from the X-ray diffraction results of the deformed specimens that the crystal structure of the stress-induced martensite phase is the orthorhombic so-called #alpha#'' structure. Within the alloys having #beta#(bcc) phase studied Nb-poor region appeared to exhibit a dominant behavior for stress-induced martensitic transformation than Nb-rich region. This result suggests that metastable #beta# phase is superior to stable #beta# phase for the occurrence of stress-induced martensitic transformation in the present ...

2007-03-25

295

Polarity of prismatic facets delimiting WC grains in WC-Co alloys  

British Library Electronic Table of Contents (United Kingdom)

This study reports a determination of the polarity of WC facets in WC-Co alloys sintered at the liquid state. In these alloys, WC grains are delimited by basal facets and two sets of {101 0} prismatic facets, one set of facets being much more developed than the other. A variation of the shape is observed as a function of the composition of the alloy. High resolution transmission electron microscopy is used to investigate the polarity of the prismatic facets owing to the typical triangular patterns appearing on the images. The effect of the composition is investigated using two alloys with different carbon potentials and one containing VC and Cr3C2 as grain growth inhibitors. The interpretation of the images shows that in all cases, the same set of prismatic planes is favoured.

2010-01-01

296

On the temperature sensing capability of a fibre optic SPR mechanism based on bimetallic alloy nanoparticles  

Energy Technology Data Exchange (ETDEWEB)

In this work, we have investigated the capability of different bimetallic nanoparticle alloy combinations to be used in fibre optic temperature sensing based on the technique of surface plasmon resonance (SPR). The metals considered for the present analysis are silver, gold and aluminium. The analysis is derived mainly from the thermo-optic effect along with some fundamental concepts of metal optics such as surface scattering, phonon-electron scattering and electron-electron scattering. The performance of the sensor with three different bimetallic nanoparticle alloy combinations is evaluated and compared, numerically, in terms of its sensitivity and accuracy. On the basis of the comparison and some logistic criterion, we predict the best possible bimetallic alloy combination along with a requisite alloy composition ratio that simultaneously provides higher values of both sensitivity and accuracy which ...

2009-02-21

297

Microstructures and tensile properties of wrought magnesium alloys processed by ECAE  

Energy Technology Data Exchange (ETDEWEB)

Magnesium alloys are ideal candidates to benefit from equal channel angular extrusion (ECAE) because of their poor forming characteristics due to a hcp structure. In this study, ECAE processing was applied to ZK31 and AZ31 magnesium alloys under various conditions. The grain size of as-ECAE specimens decreases with decreasing the processing temperature, however, the grain size decreases slightly with increasing number of repetitive processing. Both the tensile strength and 0.2% proof stress of as-ECAE specimens are high when processed at low temperature, but the elongation is high when processed at high temperature. Crystal orientation is different in the two alloys and it also varies according to the processing temperature for the two alloys. The difference of the crystal orientation influences the tensile properties, especially 0.2% proof stress. (orig.)

2003-07-01

298

Microstructural aspects of the corrosion of Alloy 800  

International Nuclear Information System (INIS)

Transmission electron microscopy studies on solution-annealed Alloy 800 revealed small (100-200 nm), spherical-shaped titanium carbide (face centered cubic structure) and large (200 nm-5 #mu#m), faceted titanium nitride (hexagonal structure) particles randomly distributed in the austenite matrix. The volume fraction of former particles was found to be greater than that of the latter. Corrosion studies of the alloy in acidic, chlorides and acidic chloride environments at room temperature indicated that the passivity of Alloy 800 was adversely affected by the addition Cl"- ions. X-ray photoelectron spectroscopy revealed that the surface film formed on the alloy at the onset of passivity consisted of Cr"3"+ (as Cr_2O_3), without any Fe"3"+/Fe"2"+ or Ni"2"+. Scanning electron microscopy studies indicated initiation of pitting at large, faceted particles, not at small, spherical-shaped ones.

2004-12-01

299

Machinability of magnesium alloy in ultra-precision diamond cutting  

Energy Technology Data Exchange (ETDEWEB)

This paper deals with an experimental study of ultra-precision diamond cutting of magnesium alloy (AZ31). In order to investigate the machinability such as the cutting force and the surface integrity and understand the problems in a micro cutting, the experiments on the diamond cutting of magnesium alloy and pure aluminum with an ultra-precision turning machine has been carried out. The machinability of magnesium alloy was compared with that of pure aluminum and discussed. Consequently, both the thrust force component and the surface roughness obtained by cutting of magnesium alloy became larger than that of pure aluminum. It was also found that the inclusions or the defects in the work material caused to generate the scratches on the finished surface and influenced the integrity of mirror surface. (orig.)

2003-07-01

300

Influence of carbon and nitrogen on corrosion resistance of high purity Fe-50mass% Cr alloys  

International Nuclear Information System (INIS)

High purity Fe-50mass%Cr alloys containing (C+N) in the range of 30 to 500 mass ppm were prepared and their corrosion resistance was investigated. Pitting potential in a 3.5mass%NaCl solution at 343K rose with reducing (C+N) content. Alloys containing (C+N) at less than 100 mass ppm did not sustain pitting corrosion. However, alloys containing 500 mass ppm (C+N) corroded severely in 6%FeCl_3+1/20N HCl solutions. Heat treatment at 923K was recognized as influencing corrosion resistance due to precipitation of carbonitrides only in the case of the alloy containing 500 mass ppm (C+N). (orig.).

301

ISO - ISO Standards - TC 156 - Corrosion of metals and alloys  

Wastenet

...ISO - ISO Standards - TC 156 - Corrosion of metals and alloys go to main navigation go to content area go to search International Standards for Business,...ISO Members FAQs Fr ISO Store Products ISO Standards By TC TC 156 Corrosion of metals and alloys ISO Store ISO Standards By ICS By ...aerospace standards Publications and e-products ISO Concept Database (ISO/CDB) Copyright TC 156 - Corrosion of metals and alloys Items to be displayed: Published ...responsibility of TC 156 Secretariat Standard and/or project Stage ICS 3ISO/WD 7441 Corrosion of metals and alloys Determination of bimetallic corrosion in outdoor ...

302

High temperature deformation of the Al-5Cr-2Zr alloy as a function of powder particle diameter  

International Nuclear Information System (INIS)

The powder particle size, D, influences the creep behaviour of Al-Cr-Zr alloys. The alloy studied in this work, Al-5Cr-2Zr (mass%), was prepared by argon atomization. Three size fractions of powder particles were selected: 24-50 #mu#m, 50-100#mu#m and 100-200 #mu#m in diameter. They were consolidated by extrusion. Independently of D, the flow behaviour of the alloy can be described by the power law equation. As test temperature increases, the stress exponent n decreases up to a value close to 5. A decrease of D causes an increase of n and delays the alloy degradation at high temperature. (Author) 11 refs.

1998-01-01

303

Development of a new Pb-free solder: Sn-Ag-Cu  

Energy Technology Data Exchange (ETDEWEB)

With the ever increasing awareness of the toxicity of Pb, significant pressure has been put on the electronics industry to get the Pb out of solder. This work pertains to the development and characterization of an alloy which is Pb-free, yet retains the proven positive qualities of current Sn-Pb solders while enhancing the shortcomings of Sn-Pb solder. The solder studied is the Sn-4.7Ag-1.7Cu wt% alloy. By utilizing a variety of experimental techniques the alloy was characterized. The alloy has a melting temperature of 217{degrees}C and exhibits eutectic melting behavior. The solder was examined by subjecting to different annealing schedules and examining the microstructural stability. The effect of cooling rate on the microstructure of the solder was also examined. Overall, this solder alloy shows great promise as a viable alternative to Pb-bearing solders and, as such, an ...

1995-02-10

304

Design and microstructural analysis of magnesium alloys for dynamical applications  

British Library Electronic Table of Contents (United Kingdom)

A microanalytical characterization of cast magnesium alloys of eutectic origin based on the Mg?Al?Ca ternary matrix system has been carried out in order to investigate the influence of alloying elements on their microstructure as well as microchemistry-processing-microstructural relations using structure-sensitive techniques of electron microscopy, mechanical spectroscopy (internal friction), X-ray diffractometry, and advanced microanalytical methods including electron probe compositional analysis. Following the data obtained here there is direct correlation of microstructure with creep properties of the new experimental magnesium alloys. The creep and heat-induced properties of the multicomponent magnesium alloys containing low range of inexpensive additions of titanium (0.07?0.2%) or str...

2011-01-01

305

Cycleable graphite/FeSi{sub 6} alloy composite as a high capacity anode material for Li-ion batteries  

Energy Technology Data Exchange (ETDEWEB)

FeSi{sub 6}/graphite composite was prepared by mechanical ball milling. The FeSi{sub 6} alloy particles consist of an electrochemically active silicon phase and inactive phases FeSi{sub 2}, distributed uniformly in the graphite matrix. The composite anode offers a large reversible capacity (about 800 mAh g{sup -1}) and good cycleability, due to the buffering effect of the inactive FeSi{sub 2} phase and graphite layers on the volumetric changes of Si phase during lithium-Si alloying reaction. Since FeSi{sub 6} alloy is a low-cost industrial material, this alloy compound provides a possible alternative for development of high capacity lithium-ion batteries. (author)

2008-10-01

306

Comparison on the growth of oxide films formed in alloy 800 and alloy 600 in an aqueous medium at high temperature  

International Nuclear Information System (INIS)

Alloy 800 and Alloy 600 are well known for their resistance to corrosion in an aqueous medium at high pressure and temperature, for which they have been widely used for more than 3 decades in different structural components of water refrigerated nuclear reactors, especially as material for the steam generator tubes (SG) in these nuclear plants. The SG tubes in the Atucha I and Embalse Nuclear Plants are made with Alloy 800. The speed of corrosion of these materials in a reactor's refrigerant medium, while very small is perfectly measurable and can be described by parabolic or logarithmic type kinetics. In other words this speed is high in the first states of growth during the formation of a protective oxide film but then drops to almost stationary values. One characteristic of these films is the formation of a double layer (or duplex): i) an internal adhering layer, of approximately constant thickness, formed by small ...

2006-12-01

307

Capacitive behaviour and electronic structure of passive films formed on nickel base alloy type Inconel 600; influence of Cr and Fe  

International Nuclear Information System (INIS)

The study of passive films formed on a nickel base alloy type Inconel 600 is performed by capacitance measurements (Mott-Schottky approach). This research is supported by the passivation study of the alloying elements Ni, Cr, Fe and high purity alloys Ni-Cr, Ni-Fe, Ni-Cr-Fe. The results obtained show that the capacitive behaviour of the Inconel 600 in the passive state is similar to that on a p-n heterojunction to which a barrier zone of nickel oxide is added. The individual or combined action of alloying elements on the development of this kind of electronic structure is discussed. (authors). 5 refs., 6 figs.

1994-01-01

308

Bulk amorphous and nanocrystalline Al83Fe17 alloys prepared by consolidation of mechanically alloyed amorphous powder  

British Library Electronic Table of Contents (United Kingdom)

In the present work, bulk amorphous and nanocrystalline Al83Fe17 alloys were obtained by consolidation of mechanically alloyed powders. Mechanical alloying of Al-17% Fe powder mixture yielded powder with an amorphous structure. Thermal behaviour of the milling product was examined using differential scanning calorimetry. This investigation revealed that the amorphous phase crystallised above 380^oC. The amorphous powder was compacted under a pressure of 7.7GPa in different conditions: at 380^oC for 600s and at 1000^oC for 180s. Structural investigations of the bulk material revealed that the amorphous structure was retained after consolidation process applied at 380^oC. Compaction under high pressure at 1000^oC caused crystallisation of the amorphous phase and appearance of metastable nano...

2010-01-01

309

Alloy 800 specifications in compliance with component requirements  

Energy Technology Data Exchange (ETDEWEB)

In view of the importance of the material Alloy 800 in high-temperature reactor plants (HTR), a material data bank was established which is used for statistical evaluation of mechanical and physical material behaviour. Based on investigations on the interconnection between the mechanical properties at high temperatures and the metallurgical parameters, different types of Alloy 800 were specified in compliance with the component requirements. In addition, aspects of corrosion and toughness behaviour were taken into consideration. The specifications and strength characteristics for the different variants of Alloy 800 were incorporated into draft DIN standards after discussion and approval in expert committees. Further important characteristics of the mechanical and physical material behaviour were summarized in HTR material data sheets so as to furnish an improved basis for the design and stress analyses of ...

1990-04-01

310

Alloy 800 specifications in compliance with component requirements  

International Nuclear Information System (INIS)

In view of the importance of the material Alloy 800 in high-temperature reactor plants (HTR), a material data bank was established which is used for statistical evaluation of mechanical and physical material behaviour. Based on investigations on the interconnection between the mechanical properties at high temperatures and the metallurgical parameters, different types of Alloy 800 were specified in compliance with the component requirements. In addition, aspects of corrosion and toughness behaviour were taken into consideration. The specifications and strength characteristics for the different variants of Alloy 800 were incorporated into draft DIN standards after discussion and approval in expert committees. Further important characteristics of the mechanical and physical material behaviour were summarized in HTR material data sheets so as to furnish an improved basis for the design and stress analyses of ...

311

A two-component Frenkel-Kontorowa model for surface alloy formation  

Energy Technology Data Exchange (ETDEWEB)

It has been shown by recent experiments that bulk immiscible metals (e.g. Ag/Cu, Ag/Co and Au/Ni) can form binary alloys on certain surfaces where the substrate mediates the elastic misfits between the two components, thus relieving the elastic strain in the overlayer. These novel surface alloys exhibit a rich phase structure. We formulate a two-component Frenkel-Kontorova model in one dimension to study surface alloy formation. This model can naturally incorporate dislocation formation that plays a crucial role in determining the actual structure of the system. Using energy minimization calculations we provide a phase diagram in terms of average alloy composition and the energy of mixing. Monte Carlo simulations were also performed to study the structure and interaction of the emerging dislocations.

2003-04-02

312

Study of superficial films and of electrochemical behaviour of some nickel base alloys and titanium base alloys in solution representation of granitic, argillaceous and salted ground waters  

Energy Technology Data Exchange (ETDEWEB)

The corrosion behaviour of the stainless steels 304, 316 Ti, 25Cr-20Ni-Mo-Ti, nickel base alloys Hastelloy C4, Inconel 625, Incoloy 800, Ti and Ti-0.2% Pd alloy has been studied in the aerated or deaerated solutions at 20/sup 0/C and 90/sup 0/C whose compositions are representative of interstitial ground waters: granitic or clay waters or salt brine. The electrochemical techniques used are voltametry, polarization resistance and complexe impedance measurements. Electrochemical data show the respective influence of the parameters such as temperature, solution composition and dissolved oxygen, addition of soluble species chloride, fluoride, sulfide and carbonates, on which depend the corrosion current density, the passivation and the pitting potential. The inhibition efficiency of carbonate and bicarbonate activities against pitting corrosion is determined. In clay water at 90/sup 0/C, Ti and Ti-Pd show very high passivation aptitude and a broad ...

1985-01-01

313

Effect of PbO on the repassivation kinetics of alloy 690  

Energy Technology Data Exchange (ETDEWEB)

Effects of PbO on the repassivation kinetics of alloy 690TT were examined using the rapid scratching electrode technique under a potentiostatic condition to elucidate the influence of PbO on SCC resistance of the alloy. The repassivation kinetics of the alloy was analyzed in terms of the current density flowing from the scratch, i(t), as a function of the charge density that has flowed from the scratch, q(t). Repassivation on the scratched surface of the alloy occurred in two kinetically different processes; passive film initially nucleated and grew according to the place exchange model in which log i(t) is linearly proportional to q(t) with a slope of 1/K, and then grew according to the high field ion conduction model in which log i(t) is linearly proportional to 1/q(t) with a slope of cBV. 1/K and cBV are parameters representing the SCC susceptibility as well as repassivation rate of the ...

2000-07-01

314

Effect of PbO on the repassivation kinetics of alloy 690  

International Nuclear Information System (INIS)

Effects of PbO on the repassivation kinetics of alloy 690TT were examined using the rapid scratching electrode technique under a potentiostatic condition to elucidate the influence of PbO on SCC resistance of the alloy. The repassivation kinetics of the alloy was analyzed in terms of the current density flowing from the scratch, i(t), as a function of the charge density that has flowed from the scratch, q(t). Repassivation on the scratched surface of the alloy occurred in two kinetically different processes; passive film initially nucleated and grew according to the place exchange model in which log i(t) is linearly proportional to q(t) with a slope of 1/K, and then grew according to the high field ion conduction model in which log i(t) is linearly proportional to 1/q(t) with a slope of cBV. 1/K and cBV are parameters representing the SCC susceptibility as well as repassivation rate of the ...

2000-08-24

315

The Effect of Recasting on Bond Strength between Porcelain and Base-Metal Alloys  

British Library Electronic Table of Contents (United Kingdom)

Abstract Purpose: Long-term success of metal ceramic restorations depends on metal ceramic bond strength. The purpose of this study was to determine whether recasting of base-metal alloys has any effect on metal ceramic bond strength. Materials and Methods: Super Cast and Verabond base-metal alloys were used to cast 260 wax patterns. The alloy specimens were equally divided into five groups and cast as: group A 0.0%, B 25%, C 50%, D 75%, and E 100% once-cast alloy. Each group was divided into two subgroups: the first group was cast with Super Cast and the second with Verabond. In each subgroup half of the cast alloys were veneered with Vita VMK 68 and the others with Ceramco 3. Results: Recasting decreased bond strength (p < 0.006) when used for 50% once-cast alloy. Group E with 100% new S...

2011-01-01

316

Surface improvement and biocompatibility of TiAl{sub 24}Nb{sub 10} intermetallic alloy using rf plasma nitriding  

Energy Technology Data Exchange (ETDEWEB)

The present work describes the surface improvement and biocompatibility of TiAl{sub 24}Nb{sub 10} intermetallic alloy using rf plasma nitriding. The nitriding process was carried out at different plasma power from 400 W to 650 W where the other plasma conditions were fixed. Grazing incidence X-ray diffractometry (GIXRD), Auger electron spectroscopy (AES), tribometer and a nanohardness tester were employed to characterize the nitrided layer. Further potentiodynamic polarization method was used to describe the corrosion behavior of the un-nitrided and nitrided alloy. It has been found that the Vickers hardness (HV) and corrosion resistance values of the nitrided layers increase with increasing plasma power while the wear rates of the nitrided layers reduce by two orders of magnitude as compared to those of the un-nitrided layer. This improvement in surface properties of the intermetallic alloy is due to formation of a thin ...

2007-09-30

317

Surface improvement and biocompatibility of TiAl_2_4Nb_1_0 intermetallic alloy using rf plasma nitriding  

International Nuclear Information System (INIS)

The present work describes the surface improvement and biocompatibility of TiAl_2_4Nb_1_0 intermetallic alloy using rf plasma nitriding. The nitriding process was carried out at different plasma power from 400 W to 650 W where the other plasma conditions were fixed. Grazing incidence X-ray diffractometry (GIXRD), Auger electron spectroscopy (AES), tribometer and a nanohardness tester were employed to characterize the nitrided layer. Further potentiodynamic polarization method was used to describe the corrosion behavior of the un-nitrided and nitrided alloy. It has been found that the Vickers hardness (HV) and corrosion resistance values of the nitrided layers increase with increasing plasma power while the wear rates of the nitrided layers reduce by two orders of magnitude as compared to those of the un-nitrided layer. This improvement in surface properties of the intermetallic alloy is due to formation of a thin modified ...

2007-09-30

318

Study of transformation behavior in a Ti-4.4 Ta-1.9 Nb alloy  

International Nuclear Information System (INIS)

An alloy of composition Ti-4.4 wt.% Ta-1.9 wt.% Nb is being developed as a structural material for corrosion applications, as titanium and its alloys possess excellent corrosion resistance in many oxidizing media. The primary physical metallurgy database for the Ti-4.4 wt.% Ta-1.9 wt.% Nb alloy is being presented for the first time. Determination of the #beta# transus, M_s temperature and classification of the alloy have been carried out, employing a variety of microscopy techniques, X-ray diffraction (XRD), micro-hardness and differential scanning calorimetry (DSC). The #beta# transition temperature or #beta# transus determined using different experimental techniques was found to agree very well with evaluations based on empirical calculations. Based on chemistry and observed room temperature microstructure, the alloy has been classified as an #alpha# + #beta# titanium ...

2005-01-15

319

Straining electrode behavior and corrosion resistance of nickel base alloys in high temperature acidic solution  

International Nuclear Information System (INIS)

Repassivation behavior and IGA resistance of nickel base alloys containing 0#approx#30 wt% chromium was investigated in high temperature acid sulfate solution. (1) The repassivation rate was increased with increasing chromium content. And so the amounts of charge caused by the metal dissolution were decreased with increasing chromium content. (2) Mill-annealed Alloy 600 suffered IGA at low pH environment below about 3.5 at the fixed potentials above the corrosion potential in 10%Na_2SO_4+H_2SO_4 solution at 598K. On the other hand, thermally-treated Alloy 690 was hard to occur IGA at low pH environments which mill-annealed Alloy 600 occurred IGA. (3) It was considered that the reason, why nickel base alloys containing high chromium content such as Alloy 690 (60%Ni-30%Cr-10%Fe) had high IGA/SCC resistance in high temperature acidic solution containing sulfate ...

1991-08-25

320

Stable atomic structure and magnetism of Pt-Cr binary surface alloys on Pt(0 0 1): First-principle calculations  

International Nuclear Information System (INIS)

The possibility of Pt-Cr surface alloys formation on Pt(0 0 1) was investigated and their magnetism was calculated by the full-potential linearized augmented plane wave (FLAPW) method with eight different atomic configurations. The most stable structure was calculated to be the Pt-segregated L1_2 ferromagnetic surface alloy. A_3B types (L1_2 or D0_2_2) were more stable compared to AB types (L1_0). It implies that the A_3B type surface alloys may be formed when depositing a monolayer of Cr on Pt(0 0 1). It was found from the total energy calculations that there exists a strong tendency of the Pt segregation. The segregation further stabilizes the surface alloy significantly. The work function of the most stable surface alloy was calculated to be 6.02 eV and the magnetic moment of the surface Cr was much enhanced to 3.3 #mu# _B. It is a quite interesting finding that the coupling ...

2006-09-01

321

SIMS study of compositional changes observed in a PuO_2 heat source cladding alloy  

International Nuclear Information System (INIS)

Secondary ion mass spectrometry (SIMS) has been used to investigate changes that occur in an advanced Ir-0.3W alloy during high temperature aging. This alloy is used to clad "2"3"8PuO_2 heat sources used in thermoelectric generators for deep space reconnaissance satellites. Long-term direct contact with PuO_2 at 1400"0C leads to physical and chemical changes within the cladding alloy that affect its metallurgical properties. SIMS was used to show that Cr, Fe, Ni, and in some cases O, diffuse from the PuO_2 into the alloy. Thorium and aluminum diffuse out of the alloy in these same regions. This SIMS study suggests that inward O diffusion and subsequent formation of ThO_2 on grain boundaries may stabilize the alloy against enhanced grain growth.

1983-10-11

322

SIMS study of compositional changes observed in a PuO/sub 2/ heat source cladding alloy  

Energy Technology Data Exchange (ETDEWEB)

Secondary ion mass spectrometry (SIMS) has been used to investigate changes that occur in an advanced Ir-0.3W alloy during high temperature aging. This alloy is used to clad /sup 238/PuO/sub 2/ heat sources used in thermoelectric generators for deep space reconnaissance satellites. Long-term direct contact with PuO/sub 2/ at 1400/sup 0/C leads to physical and chemical changes within the cladding alloy that affect its metallurgical properties. SIMS was used to show that Cr, Fe, Ni, and in some cases O, diffuse from the PuO/sub 2/ into the alloy. Thorium and aluminum diffuse out of the alloy in these same regions. This SIMS study suggests that inward O diffusion and subsequent formation of ThO/sub 2/ on grain boundaries may stabilize the alloy against enhanced grain growth.

1983-01-01

323

Optimizing the microstructure of implant alloy TiAl5Fe2.5 by microprobe analysis  

International Nuclear Information System (INIS)

For optimizing the microstructure of the (#alpha# + #beta#)-titanium alloy TiAl5Fe2.5 the content of the two alloying elements aluminium and iron in the #alpha#- and #beta#-phase was determined by microprobe analysis. The alloys with the composition of the #alpha#- and of the #beta#-phase at 850 degC TiAl6Fe0.5 (#alpha#-phase) and TiAl3.5Fe6.5 (#beta#-phase) were prepared by arc melting and rolling at 850 degC. The mechanical properties of the '#alpha#'- and of the '#beta#'-phase-alloy are compared with the properties of the (#alpha# + #beta#)-alloy TiAl5Fe2.5 in the as rolled and swaged condition and after an additional aging at 550 degC. By this optimizing process it was possible to achieve a tensile strength of Rsub(m) = 1012 N/mm"2, an yield strength of Rsub(p0.2) 954 N/mm"2 and an elongation at fracture A = 14.5% in the TiAl5Fe2.5-alloy, although the degree ...

1985-05-13

324

Optimization of INCOLOY alloy 800 mechanical properties for various power plant requirements  

International Nuclear Information System (INIS)

The AMSE Boiler Code development of design stresses and their optimization for alloys 800 and 800H for conventional and nuclear power plants have coincided with many successful trial installations of these grades of alloy 800. These trial installations, along with laboratory tests, have shown that alloy 800H can be used for long times with a retention of good mechanical properties, including ductility. While gamma prime can be formed, it soon loses its detrimental effect on ductility in service. Sensitization of the alloy also occurs but it, too, has a decreasing effect on corrosion resistance with time in service, especially at elevated temperatures. The authors discuss all of these aspects and conclude that alloy 800 perhaps with low carbon control in the annealed (1800 to 1950degF)(982 to 1066degC) condition gives the optimum combination of properties to 1050degF(566degC) and ...

325

On the evolution of quasicrystalline and crystalline phases in rapidly quenched Al-Co-Cu-Ni alloy  

International Nuclear Information System (INIS)

The occurrence of stable decagonal quasicrystalline phase in Al-Co-Ni and Al-Cu-Co alloys through conventional solidification is well established. Earlier, we have studied the effect of Cu substitution in place of Co in the Al_7_0Co_1_5Ni_1_5 alloy. Here we report the structural/micro-structural changes with substitution of Cu for Ni in rapidly solidified Al-Co-Ni alloys. The melt spun ribbons have been characterized using X-ray diffractometry, scanning and transmission electron microscopy. With an increase in Cu content in the melt spun Al_7_0Co_1_5Cu _xNi_1_5_-_x (x = 0-15 at.%) alloys, the relative amount of the decagonal phase decreased up to 10 at.% of Cu. At this composition, the quaternary alloy showed the co-existence of decagonal quasicrystal and superstructure of #tau#_3 vacancy ordered crystalline phases. The decagonal phase containing Cu showed more disordering than ...

2007-03-25

326

Hydrogen transport behavior of Timetal-21S alloy  

International Nuclear Information System (INIS)

Ti-15Mo-2.7Nb-3Al-0.2Si (Timetal-21S), a metastable #beta#-titanium alloy, is a candidate material for titanium matrix composite structures in hydrogen-fueled hypersonic planes because of its excellent formability and adequate mechanical properties in the 500--800 C temperature range. The alloy is strengthened through the precipitation of fine #alpha# particles in the #beta# matrix. The mechanical properties and microstructures are controlled by a solutionizing/aging heat treatment. A major concern in using titanium alloys in hydrogen service is the embrittlement caused by the precipitation of hydrides. It is believed that the large solubility of hydrogen in the #beta#-phase would preclude the precipitation of hydrides in Beta titanium alloys, especially at low hydrogen pressures. However, depending on the hydrogen content, a shift in the ductile/brittle transition temperatures to levels much higher ...

327

Development of a filler metal for Hastelloy alloy XR weldment  

Energy Technology Data Exchange (ETDEWEB)

The weldability and high temperature strength properties of tungsten-inert-gas (TIG) weldments of Hastelloy alloy XR were investigated by using two different heats of filler metals; the first (HXRF1) was designed on the basis of multiple regression analysis; the second (HXRF2) was the reference material. Bend tests, the FISCO cracking test and optical metallography were used to evaluate weldability. Tensile and creep tests were performed at 900deg C to evaluate high temperature strength properties. The results of weldability tests for both alloys showed good performance. The tensile properties of the weldments were remarkably improved in particular with respect to high temperature ductility. The creep rupture strength in the weldments made with alloy-designed HXRF1 was much higher than those of the Hastelloy alloy XR-II base metal with a higher B content. Furthermore, the creep properties were stable ...

1991-11-01

328

Development of a filler metal for Hastelloy alloy XR weldment  

International Nuclear Information System (INIS)

The weldability and high temperature strength properties of tungsten-inert-gas (TIG) weldments of Hastelloy alloy XR were investigated by using two different heats of filler metals; the first (HXRF1) was designed on the basis of multiple regression analysis; the second (HXRF2) was the reference material. Bend tests, the FISCO cracking test and optical metallography were used to evaluate weldability. Tensile and creep tests were performed at 900deg C to evaluate high temperature strength properties. The results of weldability tests for both alloys showed good performance. The tensile properties of the weldments were remarkably improved in particular with respect to high temperature ductility. The creep rupture strength in the weldments made with alloy-designed HXRF1 was much higher than those of the Hastelloy alloy XR-II base metal with a higher B content. Furthermore, the creep properties were stable ...

329

Critical pitting potential of aluminium alloys. Aluminum gokin no koshoku den prime i  

Energy Technology Data Exchange (ETDEWEB)

Pitting corrosion measuring method for almunum alloys sold on the market was studied. By addition of a little quantity of Cu {sup ++} ion, corrosion potential of alminum alloys rapidly approachs to pitting corrosion potential in the solution including chloride. After Cu {sup ++} ion of 5ppm is added in advance into the solution including chrolide to measure the pitting corrosion potential, alminum alloy test pieces are imersed into the solution in the atmospheric air, then the stable corrosion potential is shown after three-minite imersion, and this potential is defined to the pitting corrosion potential. The pitting corrosion potential can be easily measured by this method stated above (copper ion method). The values measured by copper ion method is comparatively agreed with that measured by the existing potentio dynamic method. The pitting corrosion potential have a straight lined relation with the logarithm of Cl {sup -} ...

1990-02-15

330

Crack tip oxidation of a superalloy in molten nitrate salt  

Energy Technology Data Exchange (ETDEWEB)

Alloy 800 has been proposed for use in the receiver tube panel arrays of advanced solar central receiver (SCR) designs. In this application the alloy will be exposed to a molten mixture of sodium and potassium nitrate salts at temperatures ranging up to approximately 600/sup 0/C While these salts are routinely used in a variety of applications including metal heat treating and process heat transfer, common industrial experience has been limited to maximum temperatures of 400/sup 0/C - 450/sup 0/C. There is, therefore, considerable interest in the compatibility of these salts with containment alloys at the higher temperatures associated with SCR designs. Additionally, the containment alloy may be subject to thermally induced fatigue damage resulting from intermittent cloud cover and diurnal cycling. Previous work has found that slower near-threshold fatigue crack growth rates (FCGR) in ...

1983-04-01

331

Constant extension rate (CERT) testing of alloy 690 and 800 nuclear steam generator tubing  

Energy Technology Data Exchange (ETDEWEB)

Constant extension rate (CERT) tests were performed on Alloy 690 and Alloy 800 nuclear steam generator tubing specimens. For the Alloy 690 specimens, tests were performed in deaerated 10% sodium hydroxide solutions at 315 deg C with a +100 mV applied potential. For the Alloy 800 specimens, tests were performed in deaerated 5% sodium hydroxide solutions at 343 deg C with no applied potential. The test specimens were machined from tubing which was produced by different manufacturing processes and in different heat treated conditions. The Alloy 690 tubing was tested in six different thermomechanical conditions, while the Alloy 800 tubing was tested in four different thermomechanical conditions. The results from the test program include a complete microstructural examination using light-optical and scanning electron microscopy. The CERT test results (such as maximum ...

1994-12-31

332

A CANDU utility perspective on using world experience to manage Alloy 800 SG tube degradation  

Energy Technology Data Exchange (ETDEWEB)

In response to European operating experience regarding Alloy 800 steam generator (SG) tube cracking, New Brunswick Power Nuclear (NBPN) recognized two important shortcomings in the industry SG technical support framework. First, information exchange networks between utilities with Alloy 800 SG tubing should be strengthened. Second and more importantly, there is a need for consistent industry guidance for Alloy 800 SG tubing degradation management, supported by clear technical bases. It is NBPN's perspective that this guidance can be improved immediately using the extensive amount of laboratory and field data that is available for Alloys 600, 690, and 800, and EPRI methodology developed to predict the performance of Alloy 690. NBPN has initiated the development of a performance-based inspection plan. This effort is based on demonstrated improvement factors for ...

2007-07-01

333

A CANDU utility perspective on using world experience to manage Alloy 800 SG tube degradation  

International Nuclear Information System (INIS)

In response to European operating experience regarding Alloy 800 steam generator (SG) tube cracking, New Brunswick Power Nuclear (NBPN) recognized two important shortcomings in the industry SG technical support framework. First, information exchange networks between utilities with Alloy 800 SG tubing should be strengthened. Second and more importantly, there is a need for consistent industry guidance for Alloy 800 SG tubing degradation management, supported by clear technical bases. It is NBPN's perspective that this guidance can be improved immediately using the extensive amount of laboratory and field data that is available for Alloys 600, 690, and 800, and EPRI methodology developed to predict the performance of Alloy 690. NBPN has initiated the development of a performance-based inspection plan. This effort is based on demonstrated improvement factors for ...

2007-08-19

334

Blood cadmium concentrations in the general population of Umbria, Central Italy  

Energy Technology Data Exchange (ETDEWEB)

The aims of this study were (a) to assess blood cadmium (B-Cd) concentrations and to establish a tentative reference interval; (b) to identify significant determinants of B-Cd, in a population from Umbria, Central Italy, which was not occupationally exposed to cadmium (Cd). Four hundred and thirty-four healthy blood-donors volunteered to answer a questionnaire and provide a blood sample for B-Cd analysis, which was performed by graphite furnace atomic absorption spectrophotometry. Blood Cd concentrations ranged from non-detectable values, i.e. below 0.1 {mu}g/l up to 3.4 {mu}g/l and were not normally distributed. The median values and the 95th percentiles were 0.7 and 2.0 {mu}g/l, respectively. Concentrations of B-Cd were more than double in smokers than in non-smokers, median values being 1.1 {mu}g/l and 0.5 {mu}g/l, respectively. In current smokers, B-Cd values correlated with the number of cigarettes smoked daily (r{sub s}=0.40, P=0.0001) ...

1999-02-02

335

Technical evaluation of Solar Cells, Inc., CdTe module and array at NREL  

Energy Technology Data Exchange (ETDEWEB)

The Engineering and Technology Validation Team at the National Renewable Energy Laboratory (NREL) conducts in-situ technical evaluations of polycrystalline thin-film photovoltaic (PV) modules and arrays. This paper focuses on the technical evaluation of Solar Cells, Inc., (SCI) cadmium telluride (CdTe) module and array performance by attempting to correlate individual module and array performance. This is done by examining the performance and stability of the modules and array over a period of more than one year. Temperature coefficients for module and array parameters (P{sub max}, V{sub oc}, V{sub max}, I{sub sc}, I{sub max}) are also calculated.

1996-05-01

336

Specific features and mechanisms of photoluminescence of nanostructured silicon carbide films grown on silicon in vacuum  

British Library Electronic Table of Contents (United Kingdom)

The light-emitting properties of cubic silicon carbide films grown by vacuum vapor phase epitaxy on Si(100) and Si(111) substrates under conditions of decreased growth temperatures (T gr ? 900?700?C) have been discussed. Structural investigations have revealed a nanocrystalline structure and, simultaneously, a homogeneity of the phase composition of the grown 3C-SiC films. Photoluminescence spectra of these structures under excitation of the electronic subsystem by a helium-cadmium laser (?excit = 325 nm) are characterized by a rather intense luminescence band with the maximum shifted toward the ultraviolet (?3 eV) region of the spectral range. It has been found that the integral curve of photoluminescence at low temperatures of measurements is split into a set of Lorentzian components. Th...

2011-01-01

337

Some lessons learned from the DOE site operator program  

Energy Technology Data Exchange (ETDEWEB)

Performance of electric vehicles (EVs) is being studied in an ongoing Site Operator Program, as part of the Electric and Hybrid Vehicle Program supported by the U.S. Department of Energy (DOE). More than 200 EVs are being operated by Site Operators in various geographical and climatic regions of the United States. Cold-weather operation of EVs is of particular interest. As expected, low temperatures affect a battery`s ability to accept a charge, which decreases EV range and increases operating costs. Battery types other than lead-acid are being evaluated such as nickel-iron, gelled electrolyte lead-acid, nickel-cadmium, and sodium-sulfur. Also, improved methods of collecting EV performance data are being implemented, thermal management systems are being tested, and a prototype ultracapacitor is being tested as a possible alternative to conventional batteries.

1995-01-01

338

Report on breast milk examinations carried out in Lower Saxony from 1987 until 1990  

International Nuclear Information System (INIS)

In the group of persistent aromatic hydrocarbons, the highest values were determined for polychlorinated biphenyls (PCB), total DDT and hexachlorobenzene (HBC). Comparisons of the relevant median values for the past six years led to the conclusion that the steep initial decline in the breast milk concentrations of DDT and HBC was followed by reductions at a much lower pace in the years after 1987. The time course of the concentration of the total PCB did not appear to follow any particular pattern. The mean contents of lead and cadmium remained by a wide margin below the threshold values for these heavy metals and thus were of no relevance from the toxicological point of view. It was found that the 134 and 137 cesium isotopes constituted no particular health hazard for breast-fed infants, as the relevant concentrations in breast milk were low. (VHE).

339

Relationships between hepatic trace element concentrations, reproductive status, and body condition of female greater scaup  

British Library Electronic Table of Contents (United Kingdom)

We collected female greater scaup (Aythya marila) on the Yukon-Kuskokwim Delta, Alaska during two breeding seasons to determine if concentrations of 18 trace elements in livers and eggs were elevated and if hepatic concentrations correlated with body condition or affected reproductive status. Fifty-six percent, 5%, and 42% of females, respectively, had elevated hepatic cadmium (Cd: >3mgg-1 dry weight [dw]), mercury (Hg: >3mgg-1dw), and selenium (Se: >10mgg-1dw). Somatic protein and lipid reserves were not correlated with hepatic Cd or Hg, but there was a weak negative correlation between protein and Se. Hepatic Cd, Hg, and Se were similar in females that had and had not initiated egg production. In a sample of six eggs, 33% and 100%, respectively, contained Se and Hg, but concentrations we...

2009-01-01

340

Private power in the country -- a chronology  

Energy Technology Data Exchange (ETDEWEB)

The chronology of installing solar power in a rural area of Ontario is described. The installation took all of seven years, and was characterized by a lot of joy, but also a lot of heartache and hardship, all of which are chronicled in this article. The project started with four solar modules generating 300 watts, nickel cadmium batteries of 225 Ah, an inverter of 600 watt, and a three-cylinder 6.5 Kw water-cooled propane generator. Today, nearly seven years later, the installation consists of 18 solar modules supplying 1350 watts of power, lead-acid batteries of 2770 Ah, a 2500 watt inverter, a one cylinder, 5.5 kw propane-gasoline generator, a heated, underground generator house, complete with an amp-hour meter and MPPT charge controller.

2003-06-30

341

Pilot project ''measurement of efficacy'' - biological monitoring of antimony pollution in the Munich test area using a standardized grass culture  

International Nuclear Information System (INIS)

This pilot project was carried out for the purpose of testing methods for active biological monitoring. It covered a period of three years (until September 1994), including two years of exposure. The measurements served to determine pollutant levels in plants used as animal fodder and dust-borne heavy metal concentrations in different sites and, on this basis, to obtain indirect information on human exposure. Among others, the pilot project investigated the suitability of Italian rye-grass as a biological indicator for aluminium, arsenic, cadmium, cobalt, chromium, copper, iron, mercury, magnesium, manganese, nickel, lead, platinum, antimony, titanium, and zinc. (orig./GL).

342

Liquid metal flow measurement by neutron radiography  

Energy Technology Data Exchange (ETDEWEB)

Visualization of a liquid metal flow and image processing methods to measure the vector field are carried out by real-time neutron radiography. The JRR-3M real-time thermal neutron radiography facility in the Japan Atomic Energy Research Institute was used. Lead-bismuth eutectic was used as a working fluid. Particles made from a gold-cadmium intermetallic compound (AuCd{sub 3}) were used as the tracer for the visualization. The flow vector field was obtained by image processing methods. It was shown that the liquid metal flow vector field was obtainable by real-time neutron radiography when the attenuation of neutron rays due to the liquid metal was less than l/e and the particle size of the tracer was larger than one image element size digitized for the image processing. (orig.).

1996-07-21

343

Liquid metal flow measurement by neutron radiography  

International Nuclear Information System (INIS)

Visualization of a liquid metal flow and image processing methods to measure the vector field are carried out by real-time neutron radiography. The JRR-3M real-time thermal neutron radiography facility in the Japan Atomic Energy Research Institute was used. Lead-bismuth eutectic was used as a working fluid. Particles made from a gold-cadmium intermetallic compound (AuCd_3) were used as the tracer for the visualization. The flow vector field was obtained by image processing methods. It was shown that the liquid metal flow vector field was obtainable by real-time neutron radiography when the attenuation of neutron rays due to the liquid metal was less than l/e and the particle size of the tracer was larger than one image element size digitized for the image processing. (orig.).

1996-07-01

344

Influence of Dopants on Characteristics of X-Ray Detectors Fabricated from Indium-, Gallium-, and Chlorine-Doped Cadmium Telluride Single Crystals  

Science.gov (United States)

Counting characteristics of X-ray detectors fabricated from indium-doped, gallium-doped, and chlorine-doped CdTe have been investigated. The detectors fabricated from indium-doped and gallium-doped crystals showed radiation-induced polarization, namely, a progressive decrease of count rate with an increase of photon fluence in the high-photon-fluence region, while the detectors fabricated from chlorine-doped crystals did not. Results from current-voltage characteristics of the detectors indicated that the different counting characteristics of these detectors originated from the difference in internal electric fields in each detector.

1995-08-01

345

Hydrogen transport and embrittlement in 300 M and AerMet100 ultra high strength steels  

Energy Technology Data Exchange (ETDEWEB)

This paper describes how hydrogen transport affects the severity of hydrogen embrittlement in 300 M and AerMet100 ultra high strength steels. Slow strain rate tests were carried out on specimens coated with electrodeposited cadmium and aluminium-based SermeTel 1140/962. Hydrogen diffusivities were measured using two-cell permeation and galvanostatic charging methods and values of 8.0 x 10{sup -8} and 1.0 x 10{sup -9} cm{sup 2} s{sup -1} were obtained for 300 M and AerMet100, respectively. A two-dimensional diffusion model was used to predict the hydrogen distributions in the SSR specimens at the time of failure. The superior embrittlement resistance of AerMet100 was attributed to reverted austenite forming around martensite laths during tempering.

2010-05-15

346

Effects of Copper, Cadmium, and Zinc on the Hatching Success of Brine Shrimp (Artemia franciscana)  

British Library Electronic Table of Contents (United Kingdom)

Previous studies indicate that the hatching success of brine shrimp (Artemia franciscana) cysts is surprisingly sensitive to ambient metal concentrations. These studies estimated median effective concentrations (EC50s) of 7, 5, and 28??g l?1 for Cd, Cu, and Zn, suggesting that the hatching end point for A. franciscana is the most sensitive tested to date for Cd and Zn in saline environments and comparable in sensitivity with the most sensitive tested to date for Cu. Furthermore, these data suggest that brine shrimp are at significant risk from Cu and Zn in Great Salt Lake (GSL), UT, where ambient concentrations as high as 10 and 14??g l?1, respectively, have been measured. Given that brine shrimp appear to be successfully reproducing in GSL, we hypothesized that these toxicity values were ...

2006-01-01

347

Determination of selected microelements in polish herbs and their infusions  

Energy Technology Data Exchange (ETDEWEB)

Ba, Cd, Cr, Cu, Fe, Ni, Pb and Zn were determined in birch leaves (Folium Betulae), dandelion roots (Radix Taraxacae), hawthorn blossom (Inflorescentia Crataegi) and their infusions by graphite furnace atomic absorption spectrometry (GFAAS) after microwave digestion of plant samples. Infusions were made from herbs according to prescription for patients, provided by the producer of medicine on the package. The results obtained were compared with daily requirements for each element. Results show high content of cadmium in the medicinal plants analyzed. The highest level in infusions was observed for Ni and Zn (over 90% of the total element concentration for Ni and in most cases over 50% for Zn), and the lowest for Cd and Pb. The calculated daily intake of majority of the analyzed elements was very low (under 1% of daily requirements)

2007-08-01

348

Characteristics and development report for the T1576 power supply and the MC3935 battery  

Energy Technology Data Exchange (ETDEWEB)

This report describes the requirements, designs, performance, and development histories for the T1576 power supply and the MC3935 rechargeable battery. These devices are used to power Permissive Action Link (PAL) ground controllers. The T1576 consists of a stainless steel container, one SA3553 connector, and one MC3935 battery. The MC3935 is a vented nickel/cadmium battery with 24 cells connected in series. It was designed to deliver 5.5 Amp-hours at 25{number_sign}C and the one-hour rate, with a nominal voltage of 28 V. The battery was designed to operate for 5 years or 500 full charge/discharge cycles. The power supply is expected to last indefinitely with replacement batteries and hardware.

1993-10-01

349

Catalytic desulfurization of organic sulfur compounds over zeolite catalysts  

Energy Technology Data Exchange (ETDEWEB)

In the dehydrodesulfurization of ethanethiol at 400/sup 0/C, the activities of sodium X, Y, and A zeolites decreased in the order given as did the activities of nickel, cobalt, zinc, cadmium, copper, silver, lead, manganese, barium, calcium, sodium, and iron Y zeolite catalysts. A volcano-shape order was observed between the catalytic activity and the electronegativity of the metal ions. The changes in the activity of hydrogen Y zeolite catalyst in ethanethiol dehydrodesulfurization and cumene dealkylation by calcination agreed with the decrease in the Broensted acidity but were independent of Lewis acidity. For hydrodesulfurization of thiophene, the activities of nickel, cobalt, copper, and silver Y zeolite catalysts decreased in the order given and were greater than for a commercial hydrodesulfurization catalyst; reduced and presulfided catalysts showed selective hydrodesulfurization activity. Addition of 5% of nickel or molybdenum oxides to cobalt or nickel Y ...

1980-01-01

350

Biosorption of heavy metal ions on Rhodobacter sphaeroides and Alcaligenes eutrophus H16  

Energy Technology Data Exchange (ETDEWEB)

A fundamental study of the application of bacteria to the recovery of toxic heavy metals from aqueous environments was carried out. The biosorption characteristics of cadmium and lead ions were determined with purple nonsulfur bacteria, Rhodobacter sphaeroides and hydrogen bacteria, Alcaligenes eutrophus H16 that were inactivated by steam sterilization. A simplified version of the metal binding model proposed by Plette et al. was used for the description of meal binding data. The results showed that the biosorption of bivalent metal ions to whole cell bodies of the bacteria was due to monodentate binding to two different types of acidic sites: carboxilic and phosphatic-type sites. The number of metal binding sites of A. eutrophus was 2.4-fold larger than that of R. sphaeroides.

1998-01-15

351

Apparatus for in situ determination of burnup cooling time and fissile content of an irradiated nuclear fuel assembly in a fuel storage pond  

Energy Technology Data Exchange (ETDEWEB)

A detector head for in situ inspection of irradiated nuclear fuel assemblies submerged in a water-filled nuclear fuel storage pond. The detector head includes two parallel arms which extend from a housing and which are spaced apart so as to be positionable on opposite sides of a submerged fuel assembly. Each arm includes an ionization chamber and two fission chambers. One fission chamber in each arm is enclosed in a cadmium shield and the other fission chamber is unshielded. The ratio of the outputs of the shielded and unshielded fission chambers is used to determine the boron content of the pond water. Correcting for the boron content, the neutron flux and gamma ray intensity are then used to verify the declared exposure, cooling time and fissile material content of the irradiated fuel assembly.

1985-04-09

352

A facile and green preparation of high-quality CdTe semiconductor nanocrystals at room temperature  

Energy Technology Data Exchange (ETDEWEB)

One chemical reagent, hydrazine hydrate, was discovered to accelerate the growth of semiconductor nanocrystals (cadmium telluride) instead of additional energy, which was applied to the synthesis of high-quality CdTe nanocrystals at room temperature and ambient conditions within several hours. Under this mild condition the mercapto stabilizers were not destroyed, and they guaranteed CdTe nanocrystal particle sizes with narrow and uniform distribution over the largest possible range. The CdTe nanocrystals (photoluminescence emission range of 530-660 nm) synthesized in this way had very good spectral properties; for instance, they showed high photoluminescence quantum yield of up to 60%. Furthermore, we have succeeded in detecting the living Borrelia burgdorferi of Lyme disease by its photoluminescence image using CdTe nanocrystals.

2008-06-18

353

XPS study of the passive films formed on nitrogen-implanted austenitic stainless steels  

Energy Technology Data Exchange (ETDEWEB)

Austenitic stainless steels (304-type) have been implanted with nitrogen ions in order to investigate the effects of implanted nitrogen on their electrochemical behaviour and on the nature of the passive film formed on the steels in acid (0.5M H{sub 2}SO{sub 4}). Alloys with two nitrogen doses have been prepared (2.5x10{sup 16} and 2x10{sup 17} N atoms/cm{sup 2}). The implanted alloys have been characterized by {sup 15}N-NRA (nuclear reaction analysis) and XPS (X-ray photoelectron spectroscopy). Alloy surfaces with well-defined N concentrations were prepared, prior to the electrochemical measurements, by argon-ion sputtering of the implanted material for a fixed time in order to reach a well-defined point on the nitrogen depth profile. The samples were then transferred without exposure to air to an electrochemical cell mounted in an inert gas glove box. The implanted nitrogen modifies the electrochemical behaviour of the ...

1992-05-01

354

XPS study of the passive films formed on nitrogen-implanted austenitic stainless steels  

International Nuclear Information System (INIS)

Austenitic stainless steels (304-type) have been implanted with nitrogen ions in order to investigate the effects of implanted nitrogen on their electrochemical behaviour and on the nature of the passive film formed on the steels in acid (0.5M H_2SO_4). Alloys with two nitrogen doses have been prepared (2.5x10"1"6 and 2x10"1"7 N atoms/cm"2). The implanted alloys have been characterized by "1"5N-NRA (nuclear reaction analysis) and XPS (X-ray photoelectron spectroscopy). Alloy surfaces with well-defined N concentrations were prepared, prior to the electrochemical measurements, by argon-ion sputtering of the implanted material for a fixed time in order to reach a well-defined point on the nitrogen depth profile. The samples were then transferred without exposure to air to an electrochemical cell mounted in an inert gas glove box. The implanted nitrogen modifies the electrochemical behaviour of the alloy. ...

1992-01-01

355

Sulfidation-resistant alloy/cladding for internal components of coal-conversion equipment. Volume 2. Cladding development. Final report  

Energy Technology Data Exchange (ETDEWEB)

An Fe-19Cr-8Al-0.5Hf alloy has been roll bonded to Alloy 800 to form a protective clad material suitable for use in coal conversion atmospheres. The commercial producibility of both the Fe-19Cr-8Al-0.5Hf alloy and the clad composite has been demonstrated. The clad composite has been shown to exhibit resistance to sulfidation in high sulfur, coal gasification atmospheres low Btu for 2000 hrs at 1800/sup 0/F (1255K). The FeCrAlHf alloy must be preoxidized in the absence of sulfur to form fully protective alumina scales on all surfaces. Useful life of the composite at temperatures of 1400 to 2000/sup 0/F (1033 to 1366K) is governed by reactions at the FeCrAlHf clad alloy 800 interface. The rate of interdiffusion decreases with increasing Ni content and a high Ni alloy such as RA333 appears to be a better substrate than Alloy 800 for a FeCrAlHf ...

1981-12-01

356

Stress corrosion cracking susceptibility of alloy 800  

Energy Technology Data Exchange (ETDEWEB)

Steam generators (SGs) in PWRs and CANDUs are designed for at least a 30-year operating life. However, in the 15-25 years that SGs tubed with Alloy 600 have operated commercially, they have experienced reduced reliability, mainly due to SG tubing degradation. One of the degradation mechanisms that Alloy 600 SG tubing has suffered from is lead-induced stress corrosion cracking (PbSCC) in AVT and near-neutral SG environments. In contrast to Alloy 600 tubing, test data obtained in high temperature water indicate that Alloy 800 is resistant to cracking by lead and lead compounds. For Alloy 800 (cold worked, shot peened), the most aggressive environment is reported to be alkaline with minor concentration of PbO (80 ppm). Work by Max Helie et al. also concluded that Alloy 800 is not sensitive to lead assisted SCC for pH values close to neutrality, whereas it could be ...

2002-07-01

357

Stress corrosion cracking susceptibility of alloy 800  

International Nuclear Information System (INIS)

Steam generators (SGs) in PWRs and CANDUs are designed for at least a 30-year operating life. However, in the 15-25 years that SGs tubed with Alloy 600 have operated commercially, they have experienced reduced reliability, mainly due to SG tubing degradation. One of the degradation mechanisms that Alloy 600 SG tubing has suffered from is lead-induced stress corrosion cracking (PbSCC) in AVT and near-neutral SG environments. In contrast to Alloy 600 tubing, test data obtained in high temperature water indicate that Alloy 800 is resistant to cracking by lead and lead compounds. For Alloy 800 (cold worked, shot peened), the most aggressive environment is reported to be alkaline with minor concentration of PbO (80 ppm). Work by Max Helie et al. also concluded that Alloy 800 is not sensitive to lead assisted SCC for pH values close to neutrality, whereas it could be ...

2002-05-05

358

Electronic structure and pitting behavior of 3003 aluminum alloy passivated under various conditions  

International Nuclear Information System (INIS)

Passivity of aluminum (Al) alloy 3003 in air and in aqueous solutions without and with chloride ions was characterized by electrochemical measurements, including cyclic polarization, electrochemical impedance spectroscopy (EIS), localized EIS and potential of zero charge, Mott-Schottky analysis and secondary ion mass spectroscopy (SIMS) technique. Stability, pitting susceptibility and repassivation ability of Al alloy 3003 under various film-forming conditions were determined. Results demonstrated that passive films formed on 3003 Al alloy in air and in Na2SO4 solution without and with NaCl addition show an n-type semiconductor in nature. The passive film formed in chloride-free solution is most stable, and that formed in chloride-containing solution is most unstable, with the film formed in air in between. Pitting of Al alloy 3003 passivated both in air and in aqueous solutions is inevitable in the ...

2009-07-01

359

Electrochemical behavior of Ti-Cr alloys in artificial saliva  

Energy Technology Data Exchange (ETDEWEB)

In this study, the corrosion behavior of commercially pure titanium (c.p. Ti), Ti-6Al-4V and five new experimental Ti-Cr alloys was evaluated through open-circuit potential (OCP) and potentiodynamic polarization measurement in an artificial saliva containing fluoride. Electron spectroscopy for chemical analysis (ESCA) was used to characterize the composition of the passive films on the alloy after potentiodynamic polarization measurement. It was found that in standard artificial saliva the OCP increases with higher Cr content in Ti-Cr alloys. In 0.5% NaF artificial saliva, the OCP decreases with decreasing Cr in Ti-Cr alloys, and all but Ti-5Cr remain consistently higher than those of c.p Ti and Ti-6Al-4V. Linear polarization results show that artificial saliva and artificial saliva containing 0.5% NaF result in different corrosion behavior in Ti-Cr alloys, c.p.Ti and Ti-6Al-4V. The ...

2009-11-13

360

Electrochemical behavior of Ti-Cr alloys in artificial saliva  

International Nuclear Information System (INIS)

In this study, the corrosion behavior of commercially pure titanium (c.p. Ti), Ti-6Al-4V and five new experimental Ti-Cr alloys was evaluated through open-circuit potential (OCP) and potentiodynamic polarization measurement in an artificial saliva containing fluoride. Electron spectroscopy for chemical analysis (ESCA) was used to characterize the composition of the passive films on the alloy after potentiodynamic polarization measurement. It was found that in standard artificial saliva the OCP increases with higher Cr content in Ti-Cr alloys. In 0.5% NaF artificial saliva, the OCP decreases with decreasing Cr in Ti-Cr alloys, and all but Ti-5Cr remain consistently higher than those of c.p Ti and Ti-6Al-4V. Linear polarization results show that artificial saliva and artificial saliva containing 0.5% NaF result in different corrosion behavior in Ti-Cr alloys, c.p.Ti and Ti-6Al-4V. The ...

2009-11-13

361

XPS study of passive films formed on molybdenum-implanted austenitic stainless steels  

Energy Technology Data Exchange (ETDEWEB)

Austenitic stainless steels have been implanted with molybdenum ions (Mo[sup +], 100 keV, 2.5 x 10[sup 16] atoms cm[sup -2]). The implanted material has been characterized by XPS and RBS. The implanted region has a thickness of [approx] 1000 A with a maximum molybdenum concentration of [approx] 9 at.% Mo located at [approx] 210 A from the surface. The effects of implanted molybdenum on the passivation of the alloy in 0.5 M H[sub 2]SO[sub 4] have been investigated by electrochemistry and XPS. After XPS analysis the samples were transferred without exposure to air into a glove-box with an inert atmosphere. The electrochemical behaviour of the alloy is significantly modified by the implanted molybdenum. The major effect is that the activation peak disappears. A bilayer structure (outer hydroxide/inner oxide) of the passive film is observed for both the implanted and non-implanted alloys and the thicknesses of the films are ...

1992-06-01

362

XPS study of passive films formed on molybdenum-implanted austenitic stainless steels  

International Nuclear Information System (INIS)

Austenitic stainless steels have been implanted with molybdenum ions (Mo"+, 100 keV, 2.5 x 10"1"6 atoms cm"-"2). The implanted material has been characterized by XPS and RBS. The implanted region has a thickness of #approx# 1000 A with a maximum molybdenum concentration of #approx# 9 at.% Mo located at #approx# 210 A from the surface. The effects of implanted molybdenum on the passivation of the alloy in 0.5 M H_2SO_4 have been investigated by electrochemistry and XPS. After XPS analysis the samples were transferred without exposure to air into a glove-box with an inert atmosphere. The electrochemical behaviour of the alloy is significantly modified by the implanted molybdenum. The major effect is that the activation peak disappears. A bilayer structure (outer hydroxide/inner oxide) of the passive film is observed for both the implanted and non-implanted alloys and the thicknesses of the films are similar. On the implanted ...

1991-10-01

363

Visualization of direct contact heat transfer between water and molten alloy  

Energy Technology Data Exchange (ETDEWEB)

We have been developing an innovative Steam Generator concept of Fast Breeder Reactors by using liquid-liquid direct contact heat transfer. In this concept, the SG shell is filled with a molten alloys, which is heated by primary sodium. Water is fed into the high temperature molten alloy, and evaporates by direct contact heating. In order to obtain the fundamental information to discuss the heat transfer mechanisms of the direct contact between the water and the alloy, this phenomenon was visualized by real-time neutron radiography. JRR-3M real-time thermal neutron radiography in Japan Atomic Energy Research Institute was used. Followings are main results. (1) The vigorous evaporation occurs in the molten alloy. This phenomena is different from the known phenomenon such as the evaporation of refrigerant R-113 in the water. (2) The evaporation in the bubble has finished in a moment due to high heat ...

1996-06-01

364

U.S. Contribution 1994 Summary Report Task T12: Compatibility and irradiation testing of vanadium alloys  

Energy Technology Data Exchange (ETDEWEB)

Vanadium alloys exhibit important advantages as a candidate structural material for fusion first wall/blanket applications. These advantages include fabricability, favorable safety and environmental features, high temperature and high wall load capability, and long lifetime under irradiation. Vanadium alloys with (3-5)% chromium and (3-5)% titanium appear to offer the best combination of properties for first wall/blanket applications. A V-4Cr-4Ti alloy is recommended as the reference composition for the ITER application. This report provides a summary of the R&D conducted during 1994 in support of the ITER Engineering Design Activity. Progress is reported for Vanadium Alloy Production, Welding, Physical Properties, Baseline Mechanical Properties, Corrosion/Compatibility, Neutron Irradiation Effects, Helium Transmutation Effects on Irradiated Alloys, and the Status of Irradiation ...

1995-03-01

365

The radiation hardening and microstructural defect evolution in ion irradiated Fe-Cr alloys with irradiation temperature  

International Nuclear Information System (INIS)

Generally, neutron, ion and electron Irradiations cause a substantial amount of hardening and significantly alter the deformation behavior of metals and alloys at relatively low irradiation temperatures. A radiation hardening is caused by the formation of microstructural defects such as dislocation loops, voids and precipitates under irradiation. Therefore, it is important to have a better knowledge of the irradiation induced microstructural defects under irradiation condition. As a part of the National mid- and long-term atomic energy R and D program, we are dealing with the radiation hardening behavior in Fe-Cr binary alloy. Fe-Cr binary alloy is a base alloy of Ferritic/Martensitic steel(F/M steel) planning to use for the Gen IV nuclear system. In this work, we investigated the radiation hardening and microstructural defect evolution in ion irradiated Fe-Cr alloys with ...

2009-05-01

366

The influence of yttrium (Y) on the corrosion of Mg-Y binary alloys  

International Nuclear Information System (INIS)

Research highlights: #-># The Y-intermetallic can accelerate corrosion and Y can increase the protectiveness of the surface layer. #-># In 0.1 M NaCl, the corrosion rate of Mg-Y alloys increased with increasing Y due to the Y intermetallic. #-># In 0.1 M NaCl, there was filiform corrosion. #-># In 0.1 M Na_2SO_4, the corrosion rate of Mg-Y alloys decreased with increasing Y in the range 3-7%Y. #-># Hydrogen evolution was observed from particular parts of the alloy surface. - Abstract: Corrosion of Mg-Y alloys was studied using electrochemical evaluations, immersion tests and direct observations. There were two important effects. In 0.1 M NaCl, the corrosion rate increased with increasing Y content due to increasing amounts of the Y-containing intermetallic. In 0.1 M Na_2SO_4, the corrosion rate decreased with increasing Y content above 3%, attributed to a more protective surface film, ...

2010-11-01

367

The Effect of Applied Pressure During Feeding of Critical Cast Aluminum Alloy Components With Particular Reference to Fatigue Resistance  

Energy Technology Data Exchange (ETDEWEB)

the medium to long freezing range alloys of aluminum such as A356, A357, A206, 319 for example are known to exhibit dispersed porosity, which is recognized as a factor affecting ductility, fracture toughness, and fatigue resistance of light alloy castings. The local thermal environment, for example, temperature gradient and freezing from velocity, affect the mode of solidification which, along with alloy composition, heat treatment, oxide film occlusion, hydrogen content, and the extent to which the alloy contracts on solidification, combine to exert strong effects on the porosity formation in such alloys. In addition to such factors, the availability of liquid metal and its ability to flow through the partially solidified casting, which will be affect by the pressure in the liquid metal, must also be considered. The supply of molten metal will thus be controlled by the volume of ...

2003-06-30

368

Synthesis of MgB{sub 2} from gas atomized Mg alloy powders and its superconductivity  

Energy Technology Data Exchange (ETDEWEB)

Superconducting MgB{sub 2} samples were prepared by the sintering of a mixture of fine Mg (or Mg alloy) powder produced by gas-atomization and B powder. The single MgB{sub 2} phase with a superconducting onset temperature of 38 K was obtained by sintering at 1073 K for the pure Mg or AZ31 alloy powders. In the case of AZ31, the superconducting MgB{sub 2} was obtained by sintering at a low temperature of 873 K for 50 h although a long sintering time of 100 h is needed to obtain a single MgB{sub 2} phase for Mg powder. This indicates that the AZ31 alloy enhances a formation rate of superconducting MgB{sub 2} at the low temperature through the formation of the partial melting phase. Thus, the gas-atomized fine Mg or AZ31 alloy powders are useful for preparation of a superconducting MgB{sub 2} and in particular AZ31 alloy is effective for the low temperature fabrication of MgB{sub 2}. ...

2003-07-01

369

Results of in-house cone-cup testing of low to high temperature SPF-alloys  

Energy Technology Data Exchange (ETDEWEB)

Material testing of SPF-sheet is usually done with coupon hot tensile testing. The optimum range of strain rates is determined with stepped strain tests. To overcome the problem of very few available testing facilities and time consuming and costly procedure, cone cup testing has been developed since long. This test can be generated directly in the workshop, no machining of samples is necessary and it is very much related to the real SPF-process. The analysis of suitable temperature and strain rate is done by simple measurement of resulting cone height. This paper describes a unique and novel variant of the above mentioned baseline design. It provides on-line data of the actual status of the cone cup forming resulting from the applied, constant pressure. Strain rate variations as a result from texture or from the alloy-related behaviour is detectable. Thinning and ''hardening'' behaviour of different alloys ...

2004-07-01

370

Research on deformation characteristic of AZ31Mg alloy and its constitutive equations  

Energy Technology Data Exchange (ETDEWEB)

Superplasticity of polycrystalline metallic materials is a phenomenon which shows hundreds to thousands of percents of large plastic deformation without necking in a steady state of low stress, when the uni-axial tensile loading is done in some special thermo-mechanical conditions (some limited ranges of properly high temperature and low strain rate). The main mechanism of superplastic phenomenon is the grain boundary sliding, while the main mechanism of usual plastic deformation is the trans-granular sliding. In this research, the possibility of superplastic deformation in a magnesium alloy (AZ31Mg alloy) was experimentally investigated, because generally speaking, the magnesium alloy whose atomic structure is hexagonal does not have enough formability in a form of trans-granular sliding mechanism. In this paper, the detail of experimental results are shown and discussed. Moreover, the constitutive equations of Mg ...

2004-07-01

371

Recent advances and developments in refractory alloys  

Energy Technology Data Exchange (ETDEWEB)

Refractory metal alloys based on Mo, W, Re, Ta, and Nb (Cb) find applications in a wide range of aerospace applications because of their high melting points and high-temperature strength. This paper, presents recent progress in understanding and applications of these alloys. Recent studies to improve the oxidation and mechanical behavior of refractory metal alloys, and particularly Nb alloys, are also discussed. Some Re structures, for extremely high temperature applications (> 2000C), made by CVD and P/M processes, are also illustrated. Interesting work on the development of new W alloys (W-HfC-X) and the characterization of some commercial refractory metals, e.g., K-doped W, TZM, and Nb-1%Zr, continues. Finally, recent developments in high temperature composites reinforced with refractory metal filaments, and refractory metal-based intermetallics, e.g., Nb{sub 3}Al, Nb{sub ...

1993-11-01

372

Promising materials for HTGR high temperature heat exchangers  

International Nuclear Information System (INIS)

The service conditions for high-temperature heat-exchangers with helium coolant of HTGRs and requirements imposed on materials for their production are discussed. The choice of nickel-base alloys with solid-solution hardening for long-term service at high temperatures is grounded. Results of study on properties and structure of types Ni-25Cr-5W-5Mo and Ni-20Cr-20W alloy in the temperature range of 900 deg. - 1,000 deg. C are given. The ageing of Ni-25Cr-5W-5Mo alloy at 900 deg. - 950 deg. C results in decreased corrosion-mechanical properties and is caused by the change of structural metal stability. Alloy with 20% tungsten retains a high stability of both structure and properties after prolonged exposure in helium at above temperatures. The alloy has also increased resistance to delayed fracture and low-cycle fatigue at high temperatures. The developed alloy of ...

1989-06-01

373

Numerical Modeling of Magnesium Alloy Sheet Metal Forming at Elevated Temperature  

International Nuclear Information System (INIS)

The development of light-weight vehicle is in great demand for enhancement of fuel efficiency and dynamic performance. The vehicle weight can be reduced effectively by using lightweight materials such as magnesium alloys. However, the use of magnesium alloys in sheet forming processes is still limited because of their low formability at room temperature and the lack of understanding of the forming process of magnesium alloys at elevated temperatures. In this study, uniaxial tensile tests of the magnesium alloy AZ31B-O at various temperatures were performed to evaluate the mechanical properties of this alloy relevant for forming of magnesium sheets. To construct a FLD (forming limit diagram), a forming limit test were conducted at temperature of 100 and 200 deg. C. For the evaluation of the effects of the punch temperature on the formability of a rectangular cup drawing with AZ31B-O, ...

2007-05-17

374

Microstructure fracture toughness and fatigue crack growth rate in titanium alloys; Proceedings of the 1987 TMS-AIME Annual Symposium, Denver, CO, Feb. 24, 25, 1987  

Science.gov (United States)

The papers contained in this volume provide an overview of recent theoretical and experimental research related to the fracture toughness and fatigue crack growth characteristics of titanium alloys. Topics discussed include room temperature fatigue crack propagation in beta-titanium alloys, fatigue crack growth rate acceleration in alpha+beta Ti alloys, influence of transformed beta microstructures on fatigue crack growth rates in Ti-6Al-4V, and the role of inclusion and pore content on the fracture toughness of powder processed blended elemental Ti-10V-2Fe-3Al. Papers are also presented on fatigue crack growth measurements in an alpha-beta titanium alloy, the effects of thermal processing variation on the properties of Ti-6Al-4V, and the effect of microstructure on ductility and fracture toughness of alpha+beta titanium alloys.

1987-01-01

375

Microstructure evolution and fracture behavior in superplastic deformation of hot-rolled AZ31 Mg alloy sheet  

Energy Technology Data Exchange (ETDEWEB)

Fine-grained AZ31 magnesium alloy sheets were prepared through hot rolling process. The superplastic properties of hot-rolled AZ31 Mg alloy was examined by uniaxial tensile tests at a temperature range 250{proportional_to}450 C and strain rate range 0.7 x 10{sup -3}{proportional_to}1.4 x 10{sup -1} s{sup -1}. Optical and scanning electronic microscope (SEM) were used to observe the microstructure evolution and fracture behavior in superplastic deformation of AZ31 Mg alloy and the values of deformation activation energy at various temperatures were calculated. It is demonstrated that, the hot-rolled AZ31 alloy begins to exhibit superplasticity from 300 C and a maximum elongation of 362.5% is obtained at 400 C and 0.7 x 10{sup -3} s{sup -1}. In the temperature range 300{proportional_to}400 C, the dominant superplastic deformation mechanism is grain boundary sliding (GBS) controlled by grain boundary ...

2005-07-01

376

Microstructural evolution of the surface of Mg-Al-based alloy by hydrogen treatment  

Energy Technology Data Exchange (ETDEWEB)

The present paper describes the development of ultra-fine grains on the surface of AZ31 alloys caused by hydrogenation and dehydrogenation treatment, so-called HDDR process. Upon hydrogenation process, disproportionation reaction occurred in forming of MgH{sub 2}, Mg{sub 0.42}Al{sub 0.58}, and Al phases. In the following desorption process, the three phases were re-solved into the AZ31 alloy. As a result of the HDDR phenomena, the grain size of AZ31 alloy powders was reduced down to about 100 nm after the heat treatment at 350 C under a hydrogen pressure of 7 MPa for 24 h. The grain size tended to be increased with increasing process temperatures. In addition, the HDDR process was also applied to AZ31 alloy plates. By the HDDR process at 450 C, the grain size was reduced to less than 500 nm, where hydrogenated layer thickness was limited to be in the range of about 20 {mu}m from the surface. The Vickers ...

2003-07-01

377

Influence of metallurgical factors on corrosion and electrochemical behavior of structural materials  

Energy Technology Data Exchange (ETDEWEB)

An analysis of the passive films formed on amorphous alloys of the system Fe-10% Cr-5% Mo-P-metalloid and Fe-10% Cr-5% Mo-B-Si revealed that they are more markedly enriched with chromium in silicon-free alloys. In silicon-containing amorphous alloys the passive films were highly enriched with silicon, which occurred in these films in the form of a corrosion product close to SiO/sub 2/. As shown by the investigations of a study of the anodic behavior of Fe/sub 40/Ni/sub 40/P/sub 14/B/sub 6/ and Fe/sub 40/Ni/sub 38/Mo/sub 4/B/sub 18/, phosphorus facilitates the passivation of amorphous alloys by reducing the solution current in the active state and enriching the surface layers of the metal in the form of a black prepassivation film which also contains nickel and iron. The behavior of Fe-Ni amorphous alloys containing only boron as metalloid additive differs little from that of ...

1986-07-01

378

Influence of metallurgical factors on corrosion and electrochemical behavior of structural materials  

International Nuclear Information System (INIS)

An analysis of the passive films formed on amorphous alloys of the system Fe-10% Cr-5% Mo-P-metalloid and Fe-10% Cr-5% Mo-B-Si revealed that they are more markedly enriched with chromium in silicon-free alloys. In silicon-containing amorphous alloys the passive films were highly enriched with silicon, which occurred in these films in the form of a corrosion product close to SiO_2. As shown by the investigations of a study of the anodic behavior of Fe_4_0Ni_4_0P_1_4B_6 and Fe_4_0Ni_3_8Mo_4B_1_8, phosphorus facilitates the passivation of amorphous alloys by reducing the solution current in the active state and enriching the surface layers of the metal in the form of a black prepassivation film which also contains nickel and iron. The behavior of Fe-Ni amorphous alloys containing only boron as metalloid additive differs little from that of crystalline alloys of ...

1986-01-01

379

Grain-boundary self-diffusion of alloy 800 and influence of S, P and C on grain-boundary diffusion and creep cavity formation in alloy 800  

Energy Technology Data Exchange (ETDEWEB)

Alloy 800 is an austenitic Fe-Ni-Cr steel containing relatively minor but important amounts of carbon, aluminium and titanium. Special grades of alloy 800 known as 800H, 800HT and 800LC differ in the concentrations of these elements. In addition to these industrial specifications, further melts were prepared containing phosphorous or sulphur. Using a radioactive tracer method the bulk and grain-boundary diffusion of {sup 59}Fe was investigated in these alloys in the temperature range 800 to 1000 C. For evaluation of the diffusion profiles the approximation of Suzuoka was used, which considers the depletion of the tracer on the surface. By autoradiography it was confirmed that such depletion occurs. In alloy 800H the activation energy of grain-boundary diffusion of {sup 59}Fe was found to be (209{+-}17) kJ/mol; dissolved elements, especially phosphorous, increase the activation energy. The same materials ...

1999-10-01

380

Grain-boundary self-diffusion of alloy 800 and influence of S, P and C on grain-boundary diffusion and creep cavity formation in alloy 800  

International Nuclear Information System (INIS)

Alloy 800 is an austenitic Fe-Ni-Cr steel containing relatively minor but important amounts of carbon, aluminium and titanium. Special grades of alloy 800 known as 800H, 800HT and 800LC differ in the concentrations of these elements. In addition to these industrial specifications, further melts were prepared containing phosphorous or sulphur. Using a radioactive tracer method the bulk and grain-boundary diffusion of "5"9Fe was investigated in these alloys in the temperature range 800 to 1000 C. For evaluation of the diffusion profiles the approximation of Suzuoka was used, which considers the depletion of the tracer on the surface. By autoradiography it was confirmed that such depletion occurs. In alloy 800H the activation energy of grain-boundary diffusion of "5"9Fe was found to be (209#+-#17) kJ/mol; dissolved elements, especially phosphorous, increase the activation energy. The same materials - aged ...

381

Grain boundary self-diffusion of alloy 800 as affected by sulphur, phosphorous and carbon  

Energy Technology Data Exchange (ETDEWEB)

Using a radioactive tracer method the bulk and grain boundary diffusion of {sup 59}Fe was determined in industrial alloy 800 and melts of alloy 800 with additional P and S in the temperature range 800 to 1000 C. The use of the approximation of Suzuoka was confirmed by autoradiographs. In alloy 800 H the activation energy of grain boundary diffusion of {sup 59}Fe is (209 {+-} 17)kJ/mol. Dissolved elements especially P increase the activation energy of the grain boundary diffusion of Fe by their segregation to the grain boundaries. In addition the influence of the grain boundary diffusion on the growth of creep cavities was investigated in the same materials, and the chemical composition of the creep cavities and grain boundaries were analysed by Auger electron spectroscopy (AES). For alloy 800 + 0.088 wt-%P an enrichment of about 14 at-%P was observed at the grain boundaries. The addition of P clearly ...

1999-08-01

382

Grain boundary self-diffusion of alloy 800 as affected by sulphur, phosphorous and carbon  

International Nuclear Information System (INIS)

Using a radioactive tracer method the bulk and grain boundary diffusion of "5"9Fe was determined in industrial alloy 800 and melts of alloy 800 with additional P and S in the temperature range 800 to 1000 C. The use of the approximation of Suzuoka was confirmed by autoradiographs. In alloy 800 H the activation energy of grain boundary diffusion of "5"9Fe is (209 #+-# 17)kJ/mol. Dissolved elements especially P increase the activation energy of the grain boundary diffusion of Fe by their segregation to the grain boundaries. In addition the influence of the grain boundary diffusion on the growth of creep cavities was investigated in the same materials, and the chemical composition of the creep cavities and grain boundaries were analysed by Auger electron spectroscopy (AES). For alloy 800 + 0.088 wt-%P an enrichment of about 14 at-%P was observed at the grain boundaries. The addition of P clearly enhances ...

1998-07-06

383

Experimental investigation on the fretting wear of alloy 800 in room remperature water  

Energy Technology Data Exchange (ETDEWEB)

Fretting wear test in room temperature water was performed to evaluate the wear coefficient of CANDU (CANadian Deuterium Uranium) steam generator (SG) tube material (Alloy 800) against 410 type martensitic stainless steels. The main focus is to compare the wear behaviors between Alloy 800 and Inconel 690. Test conditions are 10{approx}30N of normal load, 200{approx}450mm of sliding amplitude and 30Hz of frequency. The result indicated that the wear rate of Alloy 800 was higher than those of Inconel 690 at various test condition such as normal loads, sliding amplitudes etc. From the results of SEM observation, there was little evidence of plastic deformation layer that were dominantly formed on the worn surfaces of Inconel 690. Also, wear particles in Alloy 800 were released from contacting asperities deformed by severe plastic flow during fretting wear. Main cause of wear rate between ...

2002-05-01

384

Experimental investigation on the fretting wear of alloy 800 in room remperature water  

International Nuclear Information System (INIS)

Fretting wear test in room temperature water was performed to evaluate the wear coefficient of CANDU (CANadian Deuterium Uranium) steam generator (SG) tube material (Alloy 800) against 410 type martensitic stainless steels. The main focus is to compare the wear behaviors between Alloy 800 and Inconel 690. Test conditions are 10#approx#30N of normal load, 200#approx#450mm of sliding amplitude and 30Hz of frequency. The result indicated that the wear rate of Alloy 800 was higher than those of Inconel 690 at various test condition such as normal loads, sliding amplitudes etc. From the results of SEM observation, there was little evidence of plastic deformation layer that were dominantly formed on the worn surfaces of Inconel 690. Also, wear particles in Alloy 800 were released from contacting asperities deformed by severe plastic flow during fretting wear. Main cause of wear rate between ...

2002-05-01

385

Evaluation of microstructures and mechanical properties in the HAZ of SA 508 Gr.4N Low Alloy Steel  

International Nuclear Information System (INIS)

In the heat-affected zones (HAZ) of low alloy steels used for nuclear pressure vessel, microstructural changes, such as grain coarsening, carbide precipitation, and martensite formation, generally occur and cause a deterioration of toughness and an increase in sensitivity to brittle fracture. Metallographic analyses of low alloy steel welds reveal significantly different regions in HAZ microstructures. In 2-pass welds, there were seven characteristic regions in the HAZ determined by the peak temperature, to which the region was exposed during the weld thermal cycle: a coarse-grained region, a fine-grained region, an intercritical region, and subcritical region. The coarse-grained region can be categorized into four zones according to the reheating temperature as follows : an unaltered coarse-grained zone (UCGHAZ), a supercritically reheated coarse grained zone (SCRCGHAZ), an intercritically reheated coarse-grained zone (ICRCGHAZ), and an ...

2006-11-02

386

Electrochemical roles of precipitates on uniform corrosion and hydrogen pickup of zirconium alloys, 2. Roles on hydrogen pickup  

Energy Technology Data Exchange (ETDEWEB)

Substantial roles of precipitates such as Zr-Fe-Cr type intermetallic compounds on uniform corrosion and hydrogen pickup of zirconium alloys in pure water autoclave tests were investigated from an electrochemical point of view. In the previous paper, corrosion mechanism was elucidated by the anodic protection-precipitates degradation model. This paper describes the roles on hydrogen pickup. 633 K pure water autoclave test was performed on high purity zirconium, Zr-0.2Fe, Zr-0.2Cr, and Zr-0.1Fe-0.1Cr alloys. Hydrogen analysis after the corrosion test showed that hydrogen pickup ratio of Zr-0.2Fe alloy was about 80%. It was much higher than about 30% of pure Zr and about 10% of both Zr-0.2Cr and Zr-0.1Fe-0.1Cr alloys. Larger hydrogen content was introduced into Zr-0.2Fe alloy than the other ones by the cathodic hydrogen charging under coulombic equivalence. The precipitates at ...

2000-08-01

387

Electrochemical roles of precipitates on uniform corrosion and hydrogen pickup of zirconium alloys, 2. Roles on hydrogen pickup  

International Nuclear Information System (INIS)

Substantial roles of precipitates such as Zr-Fe-Cr type intermetallic compounds on uniform corrosion and hydrogen pickup of zirconium alloys in pure water autoclave tests were investigated from an electrochemical point of view. In the previous paper, corrosion mechanism was elucidated by the anodic protection-precipitates degradation model. This paper describes the roles on hydrogen pickup. 633 K pure water autoclave test was performed on high purity zirconium, Zr-0.2Fe, Zr-0.2Cr, and Zr-0.1Fe-0.1Cr alloys. Hydrogen analysis after the corrosion test showed that hydrogen pickup ratio of Zr-0.2Fe alloy was about 80%. It was much higher than about 30% of pure Zr and about 10% of both Zr-0.2Cr and Zr-0.1Fe-0.1Cr alloys. Larger hydrogen content was introduced into Zr-0.2Fe alloy than the other ones by the cathodic hydrogen charging under coulombic equivalence. The precipitates at ...

2000-08-01

388

Electrochemical roles of precipitates on uniform corrosion and hydrogen pickup of zirconium alloys, 1. Roles on corrosion  

Energy Technology Data Exchange (ETDEWEB)

Substantial roles of precipitates such as Zr-Fe-Cr type intermetallic compounds on uniform corrosion and hydrogen pickup of zirconium alloys in pure water autoclave tests were investigated from an electrochemical point of view. This paper describes the roles on corrosion. A corrosion test on precipitate-containing and precipitate-free materials made from pure zirconium and a small quantity of iron and chromium, rest potential measurements on an intermetallic compound of Zr(FeCr){sub 2} and zirconium matrix, and a galvanic coupling test of those were performed. Results showed that corrosion behavior of zirconium alloys could be attributed to the electrochemical properties of intermetallic compounds precipitated in each alloy. Namely, the cathodic and anodic polarization characteristics were associated with anodic protection provided by the precipitates on the alloys and the precipitates degradation in ...

2000-07-01

389

Electrochemical roles of precipitates on uniform corrosion and hydrogen pickup of zirconium alloys, 1. Roles on corrosion  

International Nuclear Information System (INIS)

Substantial roles of precipitates such as Zr-Fe-Cr type intermetallic compounds on uniform corrosion and hydrogen pickup of zirconium alloys in pure water autoclave tests were investigated from an electrochemical point of view. This paper describes the roles on corrosion. A corrosion test on precipitate-containing and precipitate-free materials made from pure zirconium and a small quantity of iron and chromium, rest potential measurements on an intermetallic compound of Zr(FeCr)_2 and zirconium matrix, and a galvanic coupling test of those were performed. Results showed that corrosion behavior of zirconium alloys could be attributed to the electrochemical properties of intermetallic compounds precipitated in each alloy. Namely, the cathodic and anodic polarization characteristics were associated with anodic protection provided by the precipitates on the alloys and the precipitates degradation in the ...

2000-07-01

390

Effect of solute content on plasma nitriding behavior of Fe-Cr alloys; Fe-Cr gokin purazuma chikka kyodo ni oyobosu yoshitsu nodo no eikyo  

Energy Technology Data Exchange (ETDEWEB)

It has been clarified by the present authors, based on the plasma nitriding of Fe-Cr alloys and Fe-Ti alloys carried out at the temperature under 550{degree}C hitherto, that an internal nitriding layer is formed due to the fine dispersion of the particles of Cr nitride and Ti nitride in {gamma}{prime} Fe4N layer on the specimen surface. In this study, the plasma nitriding of Fe-Cr alloys are carried out at 650{degree}C, and the effects of the solute (Cr) content on the structures, nitride and the thickness distribution are examined. The main results obtained therefrom are indicated hereafter. In accordance with the observation on the cross-sectional structure of the alloys, only the nitriding layer deduced as the dispersion and precipitation of the particles of Cr nitride from {alpha}-Fe of the mother phase is formed, while {gamma}{prime}-Fe4N layer, which is found at the temperature under 550{degree}C, ...

1996-03-15

391

Effect of minor alloying element variation on the properties of Alloy 800  

International Nuclear Information System (INIS)

Application of Alloy 800 in steam generator tubing of fast reactors, where continuous service temperature of the order of 550"0C is experienced, has been analyzed with respect to small variations in its chemical composition. Several laboratory melts of Alloy 800 have been prepared and their microstructural and mechanical property changes during simple aging and creep tests at 500 to 600"0C have been studied. It has been found that in the above temperature range precipitation of M_2_3C_6 on the grain boundaries is independent of the Ti : C ratio generally specified for Alloy 800. Gamma prime precipitation occurred in alloys containing as low as 0.5 percent Ti + Al after 1000 h of aging and was accompanied with a creep ductility decline. Upon #gamma# precipitation creep rate was retarded and its reacceleration for test times up to 8500 h at 550"0C was not observed. Based on the findings, increased Ti ...

392

Corrosion behavior of materials at high temperature by environmental oxidants containing sulfur derivatives: effects of aggressive phase composition on experimental alloys. Final report  

Energy Technology Data Exchange (ETDEWEB)

For a better understanding of sulphidation mechanisms, some alloys (alloy 600, alloy 800, Uranus S, iron-chromium-aluminium-alloy) and metals (iron, chromium, nickel, molybdenum, titanium) were tested at 773, 873, 1 073 K in gaseous sulphur dioxide. Total pressure was 760 torrs. Sulphur dioxide pressure was 760, 100 and 10 torrs. Argon, oxygen, water vapor were used, successively, as pressure complement. Oxygen supply, generally speaking cause decay of corrosion resistance in SO/sub 2/ atmospheres especially at 1 073 K with low ratio p/sub O2//P/sub SO/sub 2//. Water vapor supply act similarly. Temperature laws and pressure laws do not give monotonous rise of corrosion values. There are maximas suggesting corrosion products undertaking a volatilization process. According to test conditions, Uranus S, chromium, alloy 800 (and titanium at some extent) showed good corrosion resistance. ...

1981-01-01

393

Corrosion and mass transfer of ternary alloys (Fe-Ni-Cr) in anisothermal semi-stagnant Pb17Li  

Energy Technology Data Exchange (ETDEWEB)

Corrosion of several materials including pure metals Fe, Ni, Cr and also Fe-Cr, Fe-Ni-Cr alloys, has been studied in anisothermal Pb17Li (Tmax = 500 deg C; {Delta}T = 60 deg C). The corrosion rate of pure nickel is two orders of magnitude higher than the chromium one and about three orders of magnitude higher than the iron one. Fe-Cr alloys (1.4914) suffers a dissolution rate equal to the one of its major constituent, iron. With regard to the three austenitic materials (316L and NS20 steels, alloy 800), they exhibit a porous corrosion layer mainly constituted of ferrite but containing also a small amount of {sigma} phase in the case of the alloys with higher Ni content, NS30 steel and alloy 800. Mechanism of formation of this layer is discussed.

1990-12-31

394

Charge redistribution in ion-beam-mixed Pd-Ag alloys  

Science.gov (United States)

Charge flow and valence/d-band behavior in ion-beam-mixed (IBM) Pd1-xAgx (x = 0.5-0.9) alloys have been studied by X-ray photoemission measurement of the valence bands and of core-level binding energy shifts and X-ray absorption near-edge structure. We correlated the observed Ag 3d5/2 core-level shifts in these IBM alloys, relative to the elemental Ag, with the White Line area changes at the Pd and Ag L3-edge to investigate the charge redistribution at the Ag site. The results indicate that there is a decrease in sp-like conduction electron and a negligible change in the number of d-electrons at the Ag site upon alloying. These results are in line with our previous results in which Pd gains d-charges and loses sp-type charges. This electron redistribution due to hybridization in the alloy leads small net charge transfer from the Ag site to the Pd site in accordance with electronegativity predictions. ...

1996-08-01

395

An evaluation of corrosion resistant alloys by field corrosion test in Japanese refuse incineration plants  

Energy Technology Data Exchange (ETDEWEB)

As the first step for development of the corrosion resistant superheater tube materials of 500 C, 100 ata used in high efficient waste-to-energy plants, field corrosion tests of six conventional alloys were carried out at metal temperatures of 450 C and 550 C for 700 and 3,000 hours in four typical Japanese waste incineration plants. The test results indicate that austenitic alloys containing approximately 80 wt% [Cr+Ni] show excellent corrosion resistance. When the corrosive environment is severe, intergranular corrosion of 40{approximately}200 {micro}m depth occurs in stainless steel and high alloyed materials. It is confirmed quantitatively that corrosion behavior is influenced by environmental corrosion factors such as Cl concentration and thickness of deposits on tube surface, metal temperature, and flue gas temperature. The excellent corrosion resistance of high [Cr+Ni+Mo] alloys such as ...

1995-12-01

396

An evaluation of corrosion resistant alloys by field corrosion test in Japanese refuse incineration plants  

International Nuclear Information System (INIS)

As the first step for development of the corrosion resistant superheater tube materials of 500 C, 100 ata used in high efficient waste-to-energy plants, field corrosion tests of six conventional alloys were carried out at metal temperatures of 450 C and 550 C for 700 and 3,000 hours in four typical Japanese waste incineration plants. The test results indicate that austenitic alloys containing approximately 80 wt% [Cr+Ni] show excellent corrosion resistance. When the corrosive environment is severe, intergranular corrosion of 40#approx#200 microm depth occurs in stainless steel and high alloyed materials. It is confirmed quantitatively that corrosion behavior is influenced by environmental corrosion factors such as Cl concentration and thickness of deposits on tube surface, metal temperature, and flue gas temperature. The excellent corrosion resistance of high [Cr+Ni+Mo] alloys such as ...

1995-03-26

397

Texture development of AZ31 magnesium alloy during ECAE processing  

Energy Technology Data Exchange (ETDEWEB)

Mg-3%Al-1%Zn (AZ31) alloy was subjected to ECAE processing at 523 and 573 K. Microstructure observation and texture analysis were carried out using optical microscope and SEM-EBSD technique in order to investigate the process of microstructural changes including texture development during ECAE processing. Grain refinement during ECAE processing is enhanced by dynamic continuous recrystallization. The texture of the ECAE-processed AZ31 alloy specimens change with ECAE processing temperature, and the textural changes relate to deformation mechanisms that change with ECAE processing temperature. (orig.)

2003-07-01

398

Structural origin of optical bowing in semiconductor alloys p  

Energy Technology Data Exchange (ETDEWEB)

The principle of conservation and transferability of chemical bonds explains the recent discovery by extended x-ray absorption fine-structure measurements of two unequal anion-cation bond lengths R/sub A/C and R/sub B/C in A/sub x/B/sub 1-x/C zinc-blende semiconductor alloys despite the close adherence of the lattice constant to the average value (Vegard rule). This bond alternation, manifested as a structural distortion to a local chalcopyrite coordination around the anions, explains also most of the observed optical bowing in semiconductor alloys.

1983-08-22

399

Structural origin of optical bowing in semiconductor alloys p  

International Nuclear Information System (INIS)

The principle of conservation and transferability of chemical bonds explains the recent discovery by extended x-ray absorption fine-structure measurements of two unequal anion-cation bond lengths R/sub A/C and R/sub B/C in A/sub x/B/sub 1-x/C zinc-blende semiconductor alloys despite the close adherence of the lattice constant to the average value (Vegard rule). This bond alternation, manifested as a structural distortion to a local chalcopyrite coordination around the anions, explains also most of the observed optical bowing in semiconductor alloys.

400

Structural Phase Transition in AuZn Alloys  

Energy Technology Data Exchange (ETDEWEB)

AuxZn1-x alloys undergo a shape memory martensitic transformation whose temperature and nature (continuous or discontinuous) is strongly composition dependent. Neutron diffraction experiments were performed on single crystals of x=50 and 52 to explore the structural changes occurring at the transition temperature. A transverse modulation with wavevector q0=(1/3,1/3,0) develops below the transition temperature, with no observable change in lattice parameter. However, the Bragg peak width shows a broadening suggesting an unresolved rhombohedral distortion similar to what has been observed in NiTi-Fe alloys.

2009-05-03

401

Strain induced hardening in Ti-3Al-4V at 910 deg. C  

International Nuclear Information System (INIS)

High temperature deformation behavior of an alpha + beta titanium alloy Ti-3Al-4V has been investigated at 910 deg. C. by using the method of cross head speed cycling. On the basis of flow stress, strain rate and strain rate sensitivity data, the alloy was found to exhibit strain hardening at this temperature which resulted in degradation in superplastic properties of the alloy. A high beta-phase volume fraction and grain-growth in both alpha and beta phases were considered responsible for the observed hardening effect. (author)

402

Reversible Movement of Homogenously Nucleated Dislocations in a #beta#-Titanium Alloy  

International Nuclear Information System (INIS)

We demonstrate reversible movement of (1/2)[110](110) dislocation loops generated from nanodisturbances in a #beta#-titanium alloy. High resolution transmission electron microscope observations during an in situ tensile test found three reversible deformation mechanisms, nanodisturbances, dislocation loops and martensitic transformation, that are triggered in turn with increasing applied stress. All three mechanisms contribute to the nonlinear elasticity of the alloy. The experiments also revealed the evolution of the dislocation loops to disclination dipoles that cause severe local lattice rotations.

2009-01-30

403

Pitting corrosion of copper and copper alloys. (Latest citations from the Metals Abstracts alloys index database). Published Search  

Energy Technology Data Exchange (ETDEWEB)

The bibliography contains citations concerning the pitting corrosion of copper and copper alloys, in different media, with some references to methods for protecting against such corrosion. Included are factors contributing to the onset of pitting corrosion. Emphasis is placed on exposure to water, especially in tubing for heat exchangers and water conduits. Many of the citations present studies on exposure to sea water. Some references pertain to the detection of pitting corrosion in installations and the evaluation of the degree of pitting present. (Contains 250 citations and includes a subject term index and title list.)

1993-09-01

404

Pitting corrosion of copper and copper alloys. (Latest citations from the EI Compendex*plus database). Published Search  

Energy Technology Data Exchange (ETDEWEB)

The bibliography contains citations concerning the pitting corrosion of copper and copper alloys by different media, with some references to methods that protect against such corrosion. Included are factors contributing to the onset of pitting corrosion. Emphasis is placed on exposure to water, especially in heat exchanger tubing and water conduits. Studies are included which examine corrosion in metals containing small amonts of copper where corrosion is attributable to changes in alloying. (Contains a minimum of 158 citations and includes a subject term index and title list.)

1994-04-01

405

On the hydrogen etching mechanism in plasma nitriding of metals  

International Nuclear Information System (INIS)

Iron alloys and aluminum were nitrogen implanted in a controlled oxygen atmosphere and the role of hydrogen on the surface etching mechanisms studied. The surface composition was analyzed by in situ photoemission electron spectroscopy (XPS). In iron alloys, hydrogen strongly etches oxygen, improving nitrogen retention on the surface. On the other hand, hydrogen removes nitrogen from aluminum surfaces, with a deleterious effect on the nitriding effectiveness. The oxygen removal in iron alloys is associated with the catalytic effect of electrons in d-orbitals and the nitrogen removal in aluminum is associated with a steric effect.

2006-12-15

406

Occurrence of magnetism in superconductors  

Science.gov (United States)

We discuss how magnetic phenomena affect superconductivity in simple metals, transition metals and alloys thereof, and dilute Rare-Earth alloys. It is shown both qualitatively and quantitatively that superconductors are sensitive probes for studying itinerant spin excitations, local spin excitations associated with nearly magnetic impurities, the effect of the atomic environment on the stability of local magnetic moments, and the nature of the spin order in Rare-Earth alloys. Also, we discuss how magnetic impurities can be used to study the electronic configuration which is responsible for superconductivity in Laves-phase crystals like A-15 compounds and ..beta..-W crystals, for example.

1970-12-14

407

Mechanical properties of joints welded in halogen-containing controlled atmosphere  

International Nuclear Information System (INIS)

Studied are the mechanical properties of welded joints and heat affected zones of the Kh8N10T steel and OT4 and VT1-2 titanium alloys on welding in Ar+deltaF_6 and Ar+CCl_2F_2 mixtures contributed to a decrease of porosity. Tensile and impact tests of welded joints have revealed that additions of sulfur hexafluoride into argon causes a decrease of impact strength in titanium alloy when the tensile strength does not depend on the composition of a halogen-containing atmosphere. Freon (CCl_2F_2) additions decrease only slightly the impact strength of the investigated alloys.

408

Impacts of amorphous metal-based transformers on energy efficiency and environment  

International Nuclear Information System (INIS)

Magnetic properties of a recently developed Fe-based amorphous alloy with a high saturation induction of 1.65 T are reviewed. The increased saturation induction is fully utilized in transformers with reduced magnetic losses, physical sizes and audible noises, minimizing some of the drawbacks of amorphous metal-based transformers based on a currently available amorphous alloy. Impacts of this on the worldwide energy savings and reduction of greenhouse gas emissions are discussed. A recent effort in achieving a saturation induction beyond 1.65 T in nanocrystalline alloys is mentioned.

2008-10-01

409

Hot workability, microstructural control and rate-controlling mechanisms in cast-homogenized AZ31 magnesium alloy  

Energy Technology Data Exchange (ETDEWEB)

Optimum conditions for microstructural control in industrial hot working of cast and homogenized AZ31 magnesium alloys are evaluated by using a processing map. The recommended window for bulk metal working of this alloy is the domain in the temperature range 300-450 C and strain rate range 1-10 s{sup -1}, and the optimum processing parameters are 400 C and 10 s{sup -1}, where grain-boundary self diffusion is the rate-controlling mechanism. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

2009-03-15

410

High temperature fatigue example of creep life time prediction for grade 2 alloy 800 at 550 C  

Energy Technology Data Exchange (ETDEWEB)

Experimental data on the material characteristics of structures subjected to thermal and mechanical cycling are needed for designing structural parts for creep and creep-fatigue interaction. Moreover, high-temperature low-cycle fatigue data are not sufficient to predict the fatigue creep lifetime. In order to check the reliability of steam generators, tests on pipe materials are conducted under cyclic thermal loading. The tests have been performed on an iron-nickel chromium alloy (alloy 800). Isothermal low-cycle fatigue tests have been conducted at 550 C. 15 refs.

1994-04-01

411

Evaluation of SCC susceptibility of alloy 800 under CANDU SG secondary-side conditions  

Energy Technology Data Exchange (ETDEWEB)

As part of a coordinated program, AECL is developing a set of tools to aid with the prediction and management of steam generator performance. Although stress corrosion cracking (of Alloy 800) has not been detected in any operating steam generator, for life management it is necessary to develop mechanistic models to predict the conditions under which stress corrosion cracking is plausible. Therefore, constant extension rate tests were carried out for Alloy 800 under various steam generator crevice chemistry conditions at applied potentials. These tests were designed to evaluate the stress corrosion cracking susceptibility of Alloy 800 under CANDU( steam generator operating conditions. Based on the experimental results, the recommended electrochemical corrosion potential/pH zone for Alloy 800 determined by electrochemical polarization measurements was verified with the respect of stress corrosion cracking ...

2006-07-01

412

Evaluation of SCC susceptibility of alloy 800 under CANDU SG secondary-side conditions  

International Nuclear Information System (INIS)

As part of a coordinated program, AECL is developing a set of tools to aid with the prediction and management of steam generator performance. Although stress corrosion cracking (of Alloy 800) has not been detected in any operating steam generator, for life management it is necessary to develop mechanistic models to predict the conditions under which stress corrosion cracking is plausible. Therefore, constant extension rate tests were carried out for Alloy 800 under various steam generator crevice chemistry conditions at applied potentials. These tests were designed to evaluate the stress corrosion cracking susceptibility of Alloy 800 under CANDU( steam generator operating conditions. Based on the experimental results, the recommended electrochemical corrosion potential/pH zone for Alloy 800 determined by electrochemical polarization measurements was verified with the respect of stress corrosion cracking ...

2006-11-26

413

Energetical analysis of sensitivity of hydrogen embrittlement of ordered alloys  

Science.gov (United States)

Intermetallic compounds are regarded as highly promising for applications as high temperature structural materials. However, recent studies have demonstrated that a number of ordered alloys exhibit environmental embrittlement when tested in various environments at ambient temperature. When exposed to hydrogen gas or electrolytically charged with hydrogen, a significant ductility loss has been reported. The reaction of water vapor with reactive elements in the crack tip results in the generation of atomic hydrogen which diffuses from the surface to the interior and causes embrittlement. In this paper, the authors try to analyze the sensitivity of hydrogen embrittlement of ordered alloys based upon energetical considerations.

1993-10-01

414

Electron microscopy analysis of grain boundary structure and composition in superplastically deformed Al-Mg alloys  

Energy Technology Data Exchange (ETDEWEB)

Evaluation of grain boundary composition and structure in superplastically deformed AA5083-based alloys (Al-4.5Mg-1.6Mn-0.2Zr) was carried out in a field-emission gun transmission electron microscope (FEG-TEM). During superplastic deformation at high homologous temperatures materials undergo extensive grain boundary sliding (GBS) which creates a flow of defects in the near-boundary region. Recent literature has shown that the grain-boundary composition in Al-Mg alloys is not necessarily the same as the matrix, and that these differences can have an effect on GBS.

1996-12-31

415

Electron combinational light scattering in disordered Ti_x_-_1Fe_x alloys: theory and experiment  

International Nuclear Information System (INIS)

Theoretical description of Raman scattering in disordered alloys of Ti and Zr with transition metals of groups 5-8 of the Mendeleev Periodic System in critical range of concentrations (CRC) is given. Results of Raman scattering experiment in the system Ti_1_-_xF_x at 0.0005alloys studied near CRC is shown.

416

Effect of deformation on corrosion behavior of Ti-23Nb-0.7Ta-2Zr-O alloy  

International Nuclear Information System (INIS)

The influence of deformation on the corrosion behavior of a newly developed multifunctional beta titanium alloy Ti-23Nb-0.7Ta-2Zr-O (mol%) in Ringer's solution at 310 K was evaluated using an electron backscatter diffraction technique and electrochemical measurements. The results showed that the effect of deformation on the corrosion resistance of the beta titanium alloy is complicated. Small levels of plastic deformation are detrimental to the corrosion resistance, whereas large deformations tend to eliminate this detrimental effect.

2009-03-01

417

Effect of #alpha#-phase morphology and distribution on the tensile ductility of a metastable beta titanium alloy  

International Nuclear Information System (INIS)

In a program to develop a metastable beta alloy with improved fracture toughness, it was found that the tensile ductility of the alloy Ti-8 Mo-4.5 Cr-2.5 Al was strongly dependent on both processing history and annealing temperature. Evaluation of the microfracture mode of tensile samples by scanning electron microscope and metallographic techniques showed that the presence of a continuous grain boundary alpha is the most significant parameter controlling the ductility and is highly detrimental. It is concluded that, for optimum processing, the material must be worked prior to aging to avoid this grain boundary phase.

418

Diffusion bonding on superplastic-aluminum and -magnesium alloys  

Energy Technology Data Exchange (ETDEWEB)

The superplastic characteristics and diffusion bonding behaviors were investigated in commercial 7475 aluminum alloy and AZ31 magnesium alloy sheets. In this study, the presently used materials behaved in a superplastic manner at {proportional_to} 773 K (7475Al) and {proportional_to} 523 K (AZ31). Then, by the theoretical relationship between pressure and time, these materials were successfully diffusion bonded at the superplastic temperatures. The bonding strength was more than 65 MPa. The experimental bonding conditions in high quality joining, times and pressures, were good agreed with prediction analysis. (orig.)

2004-07-01

419

Damping measurements of the magnesium wrought alloys AZ31, AZ61 and AZ80 after indirect and hydrostatic extrusion  

Energy Technology Data Exchange (ETDEWEB)

Magnesium cast parts as well as indirectly and hydrostatically extruded profiles were used in order to investigate the influence of different microstructures on the damping behaviour of magnesium AZ-alloys. Especially, hydrostatic extrusion leads to a significant grain refinement in the extruded profile compared to indirect extrusion. Strain dependent damping measurements were carried out at room temperature using alloys AZ31, AZ61 and AZ80. Damping was determined as the logarithmic decrement of free bending beam vibrations. The results of these measurements after indirect and hydrostatic extrusion are shown and discussed. (orig.)

2005-07-01

420

Creep properties of modified 9 Cr-1 Mo steel  

Energy Technology Data Exchange (ETDEWEB)

Creep properties of modified 9 Cr-1 Mo steel, an alloy significantly improved in elevated-temperature strength over 2 1/4 Cr-1 Mo and other similar alloys, are presented here. Data are primarily on material in the normalized and tempered condition. Effects of variables such as isothermal annealing treatment, cold work, normalizing temperature, tempering temperature, notch, and biaxial stress state have also been examined. Data analysis and comparisons have shown that modified 9 Cr-1 Mo alloy is very insensitive in response to several material variables, heat treatments, and specimen design variables.

1983-01-01

421

Corrosion and protection of magnesium alloy AZ31D by a new conversion coating  

Energy Technology Data Exchange (ETDEWEB)

A chromium-free conversion coating for magnesium alloys were described. The conversion coating could be obtained when AZ31D magnesium alloy was immersed in a solution containing a manganese salt, phosphate and an inhibitor. Corrosion resistance of the chemical conversion coating was evaluated by anodizing polarization curve and salt immersion. XRD analysis showed that the conversion coating was mainly composed of Mn{sub 3}(PO{sub 4}){sub 2}. The morphology of the coating is observed by using SEM. The effect of electrolyte pH and concentration of inhibitor on coating growth are investigated. (orig.)

2003-07-01

422

Anomaliously high radiation hardening of iron-chromium alloys  

International Nuclear Information System (INIS)

Argon ions irradiation of 12% Cr steels and Fe/Cr alloys results in the hardening up to 10000 MPa. This value exceeds the hardening level even for martensitic transformation. Along with the increase of microhardness following irradiation the shape of X-ray graph of the affected materials changes considerable. Hardening value and behavior are determined by temperature radiation doze, preliminary ageing, extent of cold strain and alloying. The odserved phenomenon is supposed to be caused by irradiation-induced structural transformations. Reversibility of radiation hardening of the materials in question was observed.

423

An influence of ion bombardment on plasma nitriding process of Ti6Al14V alloy at 843 K temperature  

International Nuclear Information System (INIS)

This work presents results of investigations on d.c. glow discharge nitriding of #alpha#+#beta# Ti-6Al-4V titanium alloy. The treatment was performed at 843 K in nitrogen-hydrogen atmosphere, pressure 300 Pa. Special attention was paid to nitriding mechanism and determination of the role of ion bombarding in nitriding process of titanium alloys. Produced as a result of d.c. plasma nitriding surface layers were subjected to macroscopic observations, microstructure studies, microhardness testing and X-ray analysis. (author)

2004-06-20

424

Ab initio study of the elastic anomalies in Pd-Ag alloys  

International Nuclear Information System (INIS)

Ab initio total-energy calculations, based on the exact muffin-tin orbital method, are used to determine the elastic properties of Pd1-xAgx random alloys in the face-centered-cubic crystallographic phase. The compositional disorder is treated within the coherent-potential approximation. The single crystal and polycrystalline elastic constants and the Debye temperature are calculated for the whole range of concentration, 0?x?1. It is shown that the variation in the elastic parameters of Pd-Ag alloys with chemical composition strongly deviates from a simple linear or parabolic trend. The complex electronic origin of these anomalies is demonstrated.

2009-02-15

425

A study on the grain refining effects of carbon inoculation by C{sub 2}Cl{sub 6} addition on AZ31 magnesium alloy  

Energy Technology Data Exchange (ETDEWEB)

The effects of carbon inoculation by C{sub 2}Cl{sub 6} addition were investigated using commercial AZ31 magnesium alloy. The additions of C{sub 2}Cl{sub 6} to AZ31 magnesium alloy significantly reduce the grain size from 280 {mu}m to about 120 {mu}m and the tensile properties are also increased due to grain refinement. EPMA analysis shows that Al-C-O compounds are formed in the castings which are considered to function as nucleants. (orig.)

2003-07-01

426

A review of the behaviour of alloy 800 in liquid sodium  

International Nuclear Information System (INIS)

Although there is service experience of Alloy 800 as tubing for superheaters in conventional and nuclear (HTR) power stations and in PWR heat exchangers, there is no corresponding service experience in sodium-cooled fast reactor steam generators. However, some limited experimental studies have been made of corrosion behaviour, and of possible structure modifications and effects on mechanical properties which occur during exposure of this material to a high temperature sodium environment, and these are summarised in the paper. It is concluded that further work needs to be done before Alloy 800 can be confidently endorsed for use as tubing in fast reactor steam generators. (author).

427

iMAST Quarterly, Number 1, 1998  

Science.gov (United States)

... Airframe System Technoloqies Laser fabricated flooring Composite sandwich panels for noise control Spray formed HS aluminum alloys Protective ...

2011-05-14

428

[Magnetic thin film research]: Progress report year 2  

Energy Technology Data Exchange (ETDEWEB)

The work in the past year has primarily involved four areas of magnetic thin films: amorphous rare earth-transition metal alloys, epitaxial CoPt{sub 3} and Ni-Pt alloy thin films, amorphous rare earth doped Si (a new class of dilute magnetic semiconductor with large negative magnetoresistance which the authors have discovered), and exchange-coupled antiferromagnetic insulators. In the amorphous alloys, they made a systematic study of the effects of local anisotropy, macroscopic (perpendicular) anisotropy, and exchange constant on the fundamental (and practical) properties of these magnetic alloys, as originally described in the grant proposal. The work on the epitaxial Co-Pt (and more recently Ni-Pt) alloys was originally undertaken as a comparison study to the amorphous alloys. Crystalline Co-Pt alloys have many striking similarities to the ...

1996-09-01

429

Workability and Heat Treatment Characteristics of Beta ...  

Science.gov (United States)

... Accession Number : ADD135317. Title : Workability and Heat Treatment Characteristics of Beta Titanium Alloy, Ti-15V-3Cr-3Sn-3Al,. ...

1986-04-01

430

View larger image for ISS022-E-26137 - Earth Sciences and Image ...  

Science.gov (United States)

The Asarco-Mission complex (image left) is an active producer of copper and molybdenum (important in making steel and other metal alloys), ...

431

The estimation of lifetime distribution of Alloy 800 steam generator tubing  

Energy Technology Data Exchange (ETDEWEB)

Alloy 800 has been used for steam generator (SG) tubing for more than 30 years, primarily in CANDU reactors worldwide and in reactors in Germany. Extensive laboratory testing and in-service experience suggest that the Alloy 800 tubing has excellent resistance to corrosion-related degradation under appropriate operating conditions. In planning refurbishment of nuclear plants stations, a key concern is the longevity of existing SGs up to the 60-year lifetime of the refurbished plant. The paper reviews an existing methodology based on the concept of the improvement factor, and refines its estimation based on data specific to CANDU operating conditions. The paper presents a more advanced Bayesian probabilistic approach to estimate the degradation free lifetime distribution of Alloy 800 tubing, which is used to quantify the probability of degradation during the service life and to evaluate the impact of potential occurrences of ...

2009-10-15

432

The estimation of lifetime distribution of Alloy 800 steam generator tubing  

International Nuclear Information System (INIS)

Alloy 800 has been used for steam generator (SG) tubing for more than 30 years, primarily in CANDU reactors worldwide and in reactors in Germany. Extensive laboratory testing and in-service experience suggest that the Alloy 800 tubing has excellent resistance to corrosion-related degradation under appropriate operating conditions. In planning refurbishment of nuclear plants stations, a key concern is the longevity of existing SGs up to the 60-year lifetime of the refurbished plant. The paper reviews an existing methodology based on the concept of the improvement factor, and refines its estimation based on data specific to CANDU operating conditions. The paper presents a more advanced Bayesian probabilistic approach to estimate the degradation free lifetime distribution of Alloy 800 tubing, which is used to quantify the probability of degradation during the service life and to evaluate the impact of potential occurrences of ...

2009-10-01

433

The Effect of Morpholine/Boric Acid/Hydrazine Chemistry on ...  

Science.gov (United States)

... the effect of MBH on steam generator crevice corrosion; model boiler test results show that MBH is effective against denting corrosion and Alloy 600 ...

434

Temperature Dependent Constitutive Modeling for Magnesium Alloy Sheet  

International Nuclear Information System (INIS)

Magnesium alloys have been increasingly used in automotive and electronic industries because of their excellent strength to weight ratio and EMI shielding properties. However, magnesium alloys have low formability at room temperature due to their unique mechanical behavior (twinning and untwining), prompting for forming at an elevated temperature. In this study, a temperature dependent constitutive model for magnesium alloy (AZ31B) sheet is developed. A hardening law based on non linear kinematic hardening model is used to consider Bauschinger effect properly. Material parameters are determined from a series of uni-axial cyclic experiments (T-C-T or C-T-C) with the temperature ranging 150-250 deg. C. The influence of temperature on the constitutive equation is introduced by the material parameters assumed to be functions of temperature. Fitting process of the assumed model to measured data is presented and the results are ...

2010-06-15

435

Surface modification on magnesium alloys by coating with magnesium fluorides  

Energy Technology Data Exchange (ETDEWEB)

A new technique has been developed for improving corrosion resistance on magnesium alloys. Specimens of AZ31 magnesium alloy were dipped into molten salt of NaBF{sub 4} at 723 K for various times, and then cooled, rinsed with water, and dried in air. Corrosion resistance in the surface treated specimens was evaluated by salt immersion test using 1% NaCl solution as a time for occurring filiform corrosion. On an un-treated AZ31 alloy, the time for starting the filiform corrosion was about 1.2 ks, while on the surface treated specimen, the time was prolonged into about 1300 ks. Moreover, the surface treated specimen showed corrosion resistance in low pH solutions, such as 1% HNO{sub 3} and HCl solutions. (orig.)

2005-07-01

436

Surface modification of magnesium base alloys by gas/plasma nitridation  

Energy Technology Data Exchange (ETDEWEB)

Gas and plasma nitriding processes were executed in the magnesium with modification by titanium in search for an effective surface treatment method for magnesium alloys. Magnesium-nitrogen system has completely no solid solution or solubility, so that nitride should be only formed by eutectic reaction in the liquid phase. Hence, magnesium is difficult or nearly impossible to have its surface modified by nitriding. Addition of nitride forming element into magnesium enables us to lower the onset temperature of nitriding. Magnesium-titanium alloys with 1 to 5 wt% are yielded by the bulk mechanical alloying and, subjected to gas nitriding for various process conditions. Successful co-formation of Mg{sub 3}N{sub 2} as well as TiN becomes a proof to demonstrate the possibility of gas/plasma nitriding in the solid-state magnesium with aid of nitride former. (orig.)

2000-07-01

438

Stress, hydrogen segregation, and fracture in #alpha#-#beta# titanium alloys  

International Nuclear Information System (INIS)

Strain embrittlement in Ti base alloys during tensile testing was investigated. Results show that in an #alpha#-#beta# titanium alloy the local activity of H in alpha phase (#alpha#/sub H//sup #alpha#) increases and activity of H in beta phase (#alpha#/sub H//sup #beta#) decreases as the equiaxed #alpha# particle size decreases at constant volume fraction of phases. Thus with decreasing particle size there would be a tendency for H to move from #alpha# to #beta#, decreasing the H content of #alpha#. Also whether H tended to move from #beta# to #alpha# or from #alpha# interiors to the #alpha#-#beta# interface this tendency would be reduced by surface tension effects, making the alloy less susceptible to embrittlement.

439

Protective nitride formation on stainless steel alloys for proton exchange membrane fuel cell bipolar plates  

Energy Technology Data Exchange (ETDEWEB)

Gas nitridation has shown excellent promise to form dense, electrically conductive and corrosion-resistant Cr-nitride surface layers on Ni-Cr base alloys for use as proton exchange membrane fuel cell (PEMFC) bipolar plates. Due to the high cost of nickel, Fe-base bipolar plate alloys are needed to meet the cost targets for many PEMFC applications. Unfortunately, nitridation of Fe-base stainless steel alloys typically leads to internal Cr-nitride precipitation rather than the desired protective surface nitride layer formation, due to the high permeability of nitrogen in these alloys. This paper reports the finding that it is possible to form a continuous, protective Cr-nitride (CrN and Cr{sub 2}N) surface layer through nitridation of Fe-base stainless steel alloys. The key to form a protective Cr-nitride surface layer was found to be the initial formation of oxide during nitridation, ...

2007-01-01

440

Protective nitride formation on stainless steel alloys for proton exchange membrane fuel cell bipolar plates  

Energy Technology Data Exchange (ETDEWEB)

Gas nitridation has shown excellent promise to form dense, electrically conductive and corrosion-resistant Cr-nitride surface layers on Ni-Cr base alloys for use as proton exchange membrane fuel cell (PEMFC) bipolar plates. Due to the high cost of nickel, Fe-base bipolar plate alloys are needed to meet the cost targets for many PEMFC applications. Unfortunately, nitridation of Fe-base stainless steel alloys typically leads to internal Cr-nitride precipitation rather than the desired protective surface nitride layer formation, due to the high permeability of nitrogen in these alloys. This paper reports the finding that it is possible to form a continuous, protective Cr-nitride (CrN and Cr{sub 2}N) surface layer through nitridation of Fe-base stainless steel alloys. The key to form a protective Cr-nitride surface layer was found to be the initial formation of oxide during nitridation, ...

2007-11-22

441

Properties of the passive films formed on ferritic stainless steels in Cl/sup -/ Solutions  

Energy Technology Data Exchange (ETDEWEB)

The pitting resistance of Fe-Cr and Fe-Cr-Mo alloys has been correlated with characteristics of the passive films analyzed by Auger electron spectroscopy (AES). Increased film protectiveness as a result of increased Cr in the alloy can be directly attributed to Cr enrichment of the film and decreased film thickness. Increased Mo in the alloy or passivation at noble potentials promotes passive film resistance to breakdown, but neither does much to change the macrocharacteristics of the film. Rather, it is suggested that the roles of alloying and/or passivation conditions are related to the susceptibility and distribution of weak points of the film. In solutions in which pitting occurs, chloride is generally not incorporated into the film, suggesting that the role of halides is to interact with weak points of the film at the solution/film interface. At 260/sup 0/C, the films are much thicker and likely to ...

1986-10-01

442

Processing of Titanium Alloys.  

Science.gov (United States)

... information about, utilized, or discussed these subjects: basic topics: overview materials and material types: ti-6al-4v, ti1100, ti17 , ti6242, imi 550 ...

443

Phonon - Drag Thermopo wer in Dilute Copper Alloys - NASA ...  

Science.gov (United States)

ing materials were ASARCO, 59 purity, copper, silver and gold, while the silicon was Dow-Corning semi- conductor grade (69 purity). ...

444

Part Repairing Using A Hybrid Manufacturing System (Preprint ...  

Science.gov (United States)

... [11]Richter, K., Orban, S., and Nowotny, S., Laser cladding of the titanium alloy TI6242 to restore damaged blades, Proceedings of the 23rd ...

2007-03-01

445

Osseointegration of zirconia implants compared with titanium: an in vivo study  

UK PubMed Central (United Kingdom)

BackgroundTitanium and titanium alloys are widely used for fabrication of dental implants. Since the material composition and the surface topography of a biomaterial play a fundamental...Full Text Available

447

Mechanical deformation and tensile super-elastic behaviors of a Ti-Mo based shape memory alloy  

Science.gov (United States)

Ni-free shape memory alloys are promising functional materials for medical applications. A newly developed Ti-Mo based shape memory alloy shows superelasticity after thermomechanical treatment. However, the microstructure evolution and precipitation during thermomechanical processes are still not well understood. In the present paper, compressive deformation behavior at a series of temperatures of 298K - 973K and tensile deformation behavior of the alloy after aged at 573K - 973K have been investigated systematically. It is found that the compressive yield stress and ultimate compressive strength change with the deformation temperature. The ultimate tensile strength and yield stress of aged specimens also change with the aging temperature following a non-linear relationship. Microstructures of aged specimens as well as effects of lattice softening and aging-induced precipitates on the deformation behavior have been ...

2011-03-01

448

Materials and processing designs for high-performance magnesium alloys  

Energy Technology Data Exchange (ETDEWEB)

Materials and processing designs for advanced magnesium alloys with fine microstructures and superior properties were established by the combination of the repeated plastic working and the Mg{sub 2}Si synthesis in solid-state. The grain size was less than 1 {mu}m via RPW process due to its severe plastic working on raw powder. The hot extruded magnesium alloys produced in industries showed high ultimate tensile strength, e.g. 420{proportional_to}450 MPa, when employing Mg-Zn-Al-Ca-RE (Rare Earth) alloy coarse powder, having 0.5{proportional_to}2 mm diameter, as input materials. (orig.)

2005-07-01

449

Manufacturing of oxide-dispersion-strengthened steels with the use of preliminary surface oxidation  

British Library Electronic Table of Contents (United Kingdom)

Regularities of deformation-induced dissolution of a surface layer of iron oxides in matrixes of iron-based alloys with bcc and fcc lattices have been studied by the methods of M?ssbauer spectroscopy, transmission electron microscopy, and X-ray diffraction. A method of producing iron alloys strengthened by dispersed oxide nanoparticles and alloyed with elements possessing a high affinity to oxygen (titanium and yttrium) has been proposed, which implies a dynamic dissolution of a surface layer of iron oxides upon strong cold deformation and a precipitation of secondary yttrium and titanium nanooxides upon a subsequent high-temperature sintering of mechanically alloyed powders. There has been demonstrated a possibility of oxide strengthening of pure iron upon its interaction with air without...

2011-01-01

450

METAShield - NASA Technical Report Server (NTRS)  

Science.gov (United States)

alloy (Ti6242 or T i l 100) was utilized. Parametric studies were performed to investigate variations of displacements and stresses with sandwich and ...

451

Low cost fabrication of sheet structure using a new beta titanium alloy, Ti-15V-3Cr-3Al-3Sn  

Science.gov (United States)

Development efforts have been undertaken to improve the processing and structural efficiencies of

1982-01-01

452

Isothermal sheet formability and microstructure study of rolling processed magnesium alloy AZ31  

Energy Technology Data Exchange (ETDEWEB)

Applications of magnesium alloys are motivated mainly by their lightweight. However, manufacturing cost should also be evaluated when considering applying them. From this point of consideration, adoption of sheet forming processes, which previously have not been heavily researched, should be an option. This paper is intended to pioneer the study of the formability of magnesium alloy AZ31 out of rolled sheets at elevated temperatures. The rolled microstructures are examined and correlated with their formability. Post-forming conditions will also be investigated. The tool employed to perform the sheet forming experiments was a punchless die-setting which used pressurized gas to press the sheet into a female die cavity. This technique applied to Mg-alloy is unconventional and warrants attention for its potential utilization in the industry. (orig.)

2003-07-01

453

Investigations for judging the working behaviour of components made of alloy 800 and alloy 617 under creep stress. Untersuchungen zur Beurteilung des Betriebsverhaltens kriechbeanspruchter Bauteile aus Alloy 800 und Alloy 617  

Energy Technology Data Exchange (ETDEWEB)

The program introduced here for determining and describing the multi-axial creep of pipes is based, on the one hand, on the results of the nuclear process heat prototype plant material program and, on the other hand, on the possible load conditions which arise for evaluating accidents or extreme working situations. The basis of a theoretical description of multi-axial creep is the invariant theory in which both the von Mises configuration change hypothesis and the Norton creep law are included. Combined tension and torsion are also considered in detail, the superimposition of cyclic stresses in the tensile threshold area is discussed and cases of partial relaxation are explained. Experimental results for the discussed loads are introduced, which have led to satisfactory agreement between theory and experiment. (orig./MM).

1987-01-01

454

Investigation of passive films on nickel Alloy 690 in lead-containing environments  

Energy Technology Data Exchange (ETDEWEB)

Passive films formed on Alloy UNS N06690 were investigated in simulated crevice chemistries. It was found the role of lead in corrosion processes is strongly dependent on the pH value of the testing solutions. At pH 1.5 the effect of lead is narrowly noticeable; while at pH 12.7, lead has a significant influence on the electrochemical performance of alloy UNS N06690. The lead alters the surface morphologies at both pH and account for higher hydroxide content in the surface film at pH 12.7. The lead incorporation hinders the formation of spinel oxides during the passivation in alkaline solution. Nanoindentation tests indicate a significant lead-induced degradation in the mechanical properties of passive films. The passivation degradation is attributed to detrimental effects of lead via interrupting the dehydration process and hindering the formation of protective layers on the alloy surface.

2008-09-01

455

Investigation of erosion-corrosion of 3003 aluminum alloy in ethylene glycol-water solution by impingement jet system  

British Library Electronic Table of Contents (United Kingdom)

Erosion-corrosion (E-C) of 3003 aluminum (Al) alloy in ethylene glycol-water solutions were studied by weight-loss and electrochemical measurements as well as surface characterization through an impingement jet system. Al alloy E-C is dominated by erosion components, i.e., pure erosion and corrosion-enhanced erosion, which account for 92-97% of the total E-C rate under the various conditions in this work. Contribution from corrosion components, including pure corrosion and erosion-enhanced corrosion, is slight. With the increase of fluid flow velocity and sand concentration, the total E-C rate increases. Compared with the significant increase of the rates of erosion components, the increase of the rate of corrosion component is negligible. Upon fluid flow, passivity of Al alloy that develo...

2009-01-01

456

Interfacial ultrafine-grained structures on aluminum alloy 6061 joint and copper alloy 110 joint fabricated by magnetic pulse welding  

British Library Electronic Table of Contents (United Kingdom)

Magnetic pulse welding is a solid state impact welding process, similar to explosive welding, which produces metallurgical bond by oblique high-speed impact between two metal bodies. This violent impact removes the metal surface oxide layers and then joins the two atomic level clean metal surfaces together by the incidental compression pressure. The impact velocity is at 200?400?m/s and the being welded metal surface undergoes severe plastic deformation with strain rate in the order of 106?107?s?1. The ultrafine-grained structure was observed on the welded interface. This article studied two types of similar material lap joint interfaces and the base metals were aluminum alloy 6061 and copper alloy 110. Nano-indentation testing shows that the welded interfaces have significantly greater ha...

2010-01-01

460

Glassy Carbon, Alloys  

Science.gov (United States)

... 2.2.1 Polymerization of DVB Under Pressure DVB was polymerized at 300*C in thin-walled Pd-Ag capsules at pressures up to 60,000 psi. ...

1972-07-27

461

Friction welding of AZ31 magnesium alloy  

Energy Technology Data Exchange (ETDEWEB)

In this paper, for an acceleration of utilization of magnesium alloy which is being interested in recent years, friction welding of AZ31 magnesium alloy was carried out, and the joint performance was discussed in relation to the deformation heat input in the upset stage and upset loss as a evaluation factor. Where, the deformation heat input in the upset stage is mechanical work represented by the product of upset speed and axial pressure. As a result, it was made clear that the friction welding of AZ31 magnesium alloy was easy in the atmosphere, and good welded joints without a non- adhesion area at the weld interface could de obtained. Moreover, the evaluation factors discussed were possible to evaluate to joint performance. (orig.)

2003-07-01

462

Evaluation method for corrosion resistance of zirconium alloy  

International Nuclear Information System (INIS)

The present invention concerns a method of evaluating corrosion resistance of a zirconium alloy easily and in a short period of time. An anode polarization curve of the zirconium alloy is measured to obtain an anode polarization curve expressed by logarithm. The curve is converted to a potential-current density curve expressed by absolute values. The peak area in the curve of the converted potential-current density is indicated by numerical values. Further, the corrosion resistance of the zirconium alloy is evaluated based on the peak area converted into the numerical values as a reference. This method is based on the finding that the peak area has a close relation with nodular corrosion resistance, and the corrosion resistance can be judged with respect to a specific zircaloy-2. (T.M.).

1993-03-26

465

Effects of modification on microstructure and properties of ultrahigh carbon (1.9wt.% C) steel  

British Library Electronic Table of Contents (United Kingdom)

The effects of a modifier that contains Rare Earths (RE), low melting point alloy (Al-Bi-Sb) and Ca-Si alloy on an ultrahigh carbon steel containing 1.9wt.% C were studied. Microstructure characterization was carried out with optical microscopy (OM) and scanning electronic microscopy (SEM) combined with energy-dispersive spectrometry (EDS). Upon modification, the continuous eutectic carbide network structure was broken up and changed to a partly isolated and finer blocky structure in the as-cast alloy. Differential scanning calorimetry (DSC) revealed that the eutectoid temperature increased and the eutectic temperature decreased for the modified alloy. Modification also improved the impact toughness of the tempered steel, with a significant increase from 6.5 to 12.6Jcm^-^2, despite the har...

2011-01-01

467

Effect of welding parameters on hot cracking susceptibility of alloy 800  

Energy Technology Data Exchange (ETDEWEB)

The varestraint cracking test was carried out to assess the hot cracking tendency of alloy 800 at different welding conditions and augmented strain levels. The test results revealed that the hot cracking susceptibility of alloy 800 increases with increasing the heat input and augmented strain levels. This emphasizes the role of constraint either internally induced or externally applied to the welded structure. A cracking threshold or the minimum augmented strain ([epsilon][sub min]) below which no hot cracking takes place has been found to be 0.25 for alloy 800. Also, the Critical Strain Rate to Time (CSS) required to cause cracking was found to be 6.42x10[sup -3] sec[sup -1] at welding condition of 100 Amp, 13 Volt and 140 mm/min. (author).

1994-08-01

468

Effect of welding parameters on hot cracking susceptibility of alloy 800  

International Nuclear Information System (INIS)

The varestraint cracking test was carried out to assess the hot cracking tendency of alloy 800 at different welding conditions and augmented strain levels. The test results revealed that the hot cracking susceptibility of alloy 800 increases with increasing the heat input and augmented strain levels. This emphasizes the role of constraint either internally induced or externally applied to the welded structure. A cracking threshold or the minimum augmented strain (#epsilon#_m_i_n) below which no hot cracking takes place has been found to be 0.25 for alloy 800. Also, the Critical Strain Rate to Time (CSS) required to cause cracking was found to be 6.42x10"-"3 sec"-"1 at welding condition of 100 Amp, 13 Volt and 140 mm/min. (author).

469

Effect of chemical composition on the structure and mechanical properties of Mn-Al-C alloys in the magnetic region  

Energy Technology Data Exchange (ETDEWEB)

The thermal stability and deformability of Mn-Al-C alloys containing 0.6 pct C are investigated experimentally as a function of excess phase content. It is shown that an increase in Mn content from 68.9 to 73.5 pct leads to increased stability of the high-temperature epsilon phase. The enrichment of the system Mn-Al-Cu in Mn and Al above the optimum composition leads to the formation of nonmagnetic excess phases, eta and beta, which reduce the magnetization of the alloy. In addition, a decrease in thermal stability is observed in the alloy with 73.5 pct Mn due to the decomposition of the ferromagnetic phase. 7 references.

1988-01-01

470

Effect of alloying on the phase transformations and properties of a nickel alloy  

Energy Technology Data Exchange (ETDEWEB)

The phase transformations and properties of a precipitation-hardened Ni-Cr-based alloy are investigated as a function of C, B, Nb, and Cr contents. It is found that the primary role of Nb consists in the formation of an independent phase, delta-Ni3Nb, a part of a gamma/gamma-prime-delta eutectoid (for high C and B concentrations) and in stimulating the gamma-sigma reaction consecutively with the gamma double prime-delta reaction (for low C and B concentrations). In both cases, the long-term strength characteristics of the Nb-alloyed system are relatively low. The substitution of boron for carbon contributes to a reduction in the number of nucleation sites for topologically close-packed phases and to the formation of more stable (with respect to excess compounds) M3B2 and MB2 borides. The high-boron material exhibits better properties and phase stability under mechanical and thermal loading. 13 references.

1986-07-01

471

ELECTRICAL AND OPTICAL PROPERTIES OF LEAD-TIN ...  

Science.gov (United States)

... Abstract : Single crystals of Pb(x)Sn(1-x)Te alloy have been grown with o = or thin film evaporator. ...

1969-09-03

472

Dual-ion irradiation effects on microstructure of austenitic alloys  

International Nuclear Information System (INIS)

An Fe-15Cr-20Ni ternary model alloy and a Type 316 stainless steel were irradiated by dual-ions at 1 to 50 appm of He/dpa ratios, to investigate the helium effects on microstructural development in austenitic alloys under irradiation. Quantitative analysis on resultant microstructures revealed that the Frank loop nucleation rate and the network dislocation density positively correlate and Frank loop growth rate negatively correlate with the He/dpa ratio, while the cavity growth rate has its peak at an intermediate helium injection rate. Although He/dpa dependence of various microstructural features were similar for the model alloy and the 316SS, the rates of their development and the mechanism which had assisted cavity growth were significantly different in these two materials. (orig.).

473

Development of materials resistant to metal dusting degradation.  

Energy Technology Data Exchange (ETDEWEB)

Metal dusting corrosion has been a serious problem in the petroleum and petrochemical industries, such as reforming and syngas production systems. This form of deterioration has led to worldwide material loss for 50 years. For the past three years, we have studied the mechanism of metal dusting for Fe- and Ni-base alloys. In this report, we present a correlation between the weight loss and depth of pits that form in Ni-base alloys. Nickel-base alloys were also tested at 1 and 14.8 atm (210 psi), in a high carbon activity environment. Higher system pressure was found to accelerate corrosion in most Ni-base alloys. To reduce testing time, a pre-pitting method was developed. Mechanical scratches on the alloy surface led to fast metal dusting corrosion. We have also developed preliminary data on the performance of weldments of several Ni-base alloys in a metal ...

2006-04-24

474

Creep performance and microstructure of the iron alloy Alloy 800 HT  

International Nuclear Information System (INIS)

The examination of the high-temperature properties of the alloy Alloy 800HT has shown that both the creep performance and the microstructure of the material can be purposefully set by the initial heat treatment. At the high temperatures applied, (700-900 C), a rapid softening process sets in induced by carbide precipitation, stabilization, and coarsening. This softening process causes creep velocities strongly accelerating as a function of duration of the heat treatment prior to the creep test. The identified cause of the softening effect is a change in particle size that could be verified by SEM and TEM. It is shown that two different carbide precipitate size classes are responsible for the softening effect. While the precipitates dectable by TEM become effective primarily via interactions with dislocations, the carbide precipitates detectable only by SEM contribute to a hardening of the grain boundaries and the matrix.(orig./CB)

1997-11-28

475

Corrosion resistance of materials of construction for high temperature sulfuric acid service in thermochemical IS process. Alloy 800, Alloy 600, SUSXM15J1 and SiC  

International Nuclear Information System (INIS)

Exposure tests of candidate materials were carried out up to 1000 hr in the sulfuric acid environments of thermochemical hydrogen production IS process, focusing on the corrosion of welded portion and of crevice area. In the gas phase sulfuric acid decomposition condition at 850degC, welded samples of Alloy 800 and of Alloy 600 showed the same good corrosion resistance as the base materials. In the boiling condition of 95 wt% sulfuric acid solution, test sample of SiC showed the same good corrosion resistance. Also negligible corrosion was observed in crevice corrosion. (author)

2006-07-01

476

Corrosion fatigue of magnesium alloys  

Energy Technology Data Exchange (ETDEWEB)

To study the fatigue life of extruded AZ31 (3%Al, 1%Zn, 0.3%Mn, Mg - the rest), AM50 (5%Al, 0.4%Mn, Mg - the rest) and ZK60 (5%Zn, 0.5%Zr, Mg - the rest) Mg alloys in air and NaCl-based solutions, corrosion fatigue tests were carried out using a rotating beam type fatigue machine. For the analysis of the corrosion fatigue behavior of Mg alloys in different environments, fitted N{sub sol}/N{sub air} ratio considered as a relative corrosion fatigue life is used. Here N{sub sol} and N{sub air} are the numbers of cycles to failure in the solution and in air, respectively. An extruded ZK60 alloy shows very high fatigue and corrosion fatigue properties in comparison with other alloys. However, ZK60 shows the lowest values of the relative fatigue life (N{sub sol}/N{sub air} {proportional_to}10{sup -3}-10{sup -2}) compared to that for AM50 and AZ31 alloys (N{sub sol}/N{sub air} ...

2003-07-01

477

Corrosion behaviour of Alloy 800 in high temperature aqueous solutions: Electrochemical studies  

International Nuclear Information System (INIS)

The anodic behaviour and passivity breakdown of Alloy 800 in aqueous solutions of sodium chloride, sodium sulphate and sodium bicarbonate were studied by electrochemical techniques in the temperature range from 60 C to 280 C. The pitting resistance and pitting morphology of the alloy in chloride plus sulphate and chloride plus bicarbonate mixtures, at 60 C and 280 C, were also examined. Increasing bicarbonate or sulphate additions to chloride solutions shift the characteristic pitting potential of Alloy 800 to higher values, both at low and high temperatures. Changes in pitting morphology were observed in sulphate containing solutions while the morphology of the attack found in bicarbonate containing solutions was similar to that in pure chloride solutions. Finally, no localized or substantial generalized corrosion was detected in pure sulphate or bicarbonate solutions at any temperature. (orig.).

478

Corrosion behaviors of Zn/Al-Mn alloy composite coatings deposited on magnesium alloy AZ31B (Mg-Al-Zn)  

International Nuclear Information System (INIS)

After being pre-plated a zinc layer, an amorphous Al-Mn alloy coating was applied onto the surface of AZ31B magnesium alloy with a bath of molten salts. Then the corrosion performance of the coated magnesium alloy was examined in 3.5% NaCl solution by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The results showed that the single Zn layer was active in the test solution with a high corrosion rate while the Al-Mn alloy coating could effectively protect AZ31B magnesium alloy from corrosion in the solution. The high corrosion resistance of Al-Mn alloy coating was ascribed to an intact and stable passive film formed on the coating. The performances of the passive film on Al-Mn alloy were further investigated by Mott-Schottky curve and X-ray photoelectron spectroscopy (XPS) analysis. It was confirmed that the ...

2009-12-30

479

Corrosion behavior of iron and nickel base alloys in high temperature and pressure water  

International Nuclear Information System (INIS)

In equipment industries, the equipments handling industrial water and pure water are numerous. In power generation including nuclear power generation, water serves as a working medium. Review is made on the experiences in the corrosion of iron and nickel base alloys in high temperature, high pressure water and the results of researches derived from them. Under high temperature and high pressure, carbon steel, low alloy steel, stainless steel and high nickel alloy cause corrosion even in pure water. But in the case of serious corrosion, chlorine, oxygen, alkali and others in water take part. The following matters are described: corrosion by steam; stress corrosion cracking in pure water; corrosion by impurities in high temperature, high pressure pure water, i.e. chlorine ions, dissolved oxygen, and alkali; corrosion under radiation. (J.P.N.).

480

Commercial Contract Training, Marine Corps Area VOTEC ...  

Science.gov (United States)

... Plaster Foundry facings_ Casting: (Non-ferrous Ferrous Alloy .___) Cupola furnace Core baking oven_ _ Metallurgy__ Thermite casting__ ...

1975-06-01

481

Chemical composition and electronic structure of passive films formed on Alloy 600 in acidic solution  

Energy Technology Data Exchange (ETDEWEB)

The chemical composition and the semiconducting properties of passive films formed on nickel based alloy (Alloy 600) in acidic sulphate solution, pH 2.0 at room temperature were studied using Auger analysis, voltammetric techniques and the Mott-Schottky approach. The results obtained revealed that the presence of both chromium and mixed nickel-iron oxides in the films leads to the development of a p-n heterojunction, which controls their electronic structure, similarly manner to the case of stainless steels and Alloy 600 in borate buffer solution. This behavior has been interpreted as representing of an oxide system, which has a duplex character, with an inner p-type semiconducting region, mainly formed by chromium oxide and an outer n-type semiconducting region, containing iron oxide. It could also be observed that the nickel oxide present in the films acts as a barrier layer conferring improved protection.

2008-03-15

482

Chemical composition and electronic structure of passive films formed on Alloy 600 in acidic solution  

International Nuclear Information System (INIS)

The chemical composition and the semiconducting properties of passive films formed on nickel based alloy (Alloy 600) in acidic sulphate solution, pH 2.0 at room temperature were studied using Auger analysis, voltammetric techniques and the Mott-Schottky approach. The results obtained revealed that the presence of both chromium and mixed nickel-iron oxides in the films leads to the development of a p-n heterojunction, which controls their electronic structure, similarly manner to the case of stainless steels and Alloy 600 in borate buffer solution. This behavior has been interpreted as representing of an oxide system, which has a duplex character, with an inner p-type semiconducting region, mainly formed by chromium oxide and an outer n-type semiconducting region, containing iron oxide. It could also be observed that the nickel oxide present in the films acts as a barrier layer conferring improved protection.

2008-03-01

483

Caustic stress corrosion cracking studies at 288 C (550 F) using the straining electrode technique--comparison of Alloy 600, Alloy 800, and Type 304 stainless steel  

International Nuclear Information System (INIS)

Constant pull rate tests were conducted on tensile specimens of Inconel Alloy 600, Incoloy Alloy 800, and Type 304 stainless steel in deaerated 10% NaOH solution at 288 C (550 F) with a cover gas of 5% H_2 in N_2. The pull rate used for most experiments was 3.3 x 10"-"6 cm/s, which corresponds to an initial strain rate of 3 x 10"-"6 s"-"1. The electrical potential of the specimens was controlled by a potentiostat using a nickel wire as a hydrogen reference electrode. Under open circuit conditions, Type 304 stainless steel specimens cracked rapidly, but Alloys 600 and 800 specimens exhibited only ductile fracture. However, cracks readily formed in Alloy 800 specimens at potentials in the +50 to +300 mV range and in Alloy 600 specimens at potentials in the +150 to +250 mV range. Scanning electron microscope (SEM) photographs of some of the cracked specimen surfaces showed the ...

484

Carnegie -Mellon University - NASA Technical Report Server (NTRS)  

Science.gov (United States)

Procedures for a New High-Strength, Beta Titanium Alloy having. Superior Formability, " Technical Report AFML-TR-69-171, Air ...

485

Blow forming of recycled 5083 Al alloy and AZ31Mg alloy by solid state recycling  

Energy Technology Data Exchange (ETDEWEB)

Blow forming characteristics of 5083 Al alloy and AZ31 Mg alloy recycled by solid state recycling were investigated. Scraps with different volume were recycled by hot extrusion and hot rolling in air. Oxide layers, which were contaminants from scrap surface, were distributed parallel to the extrusion direction in the recycled specimens. In the blow-forming test, the specimen from smaller scraps exhibited lower formability. The oxygen concentration in the recycled specimens was approximately proportional to the total surface area of scraps in the recycled specimen per unit volume. The low formability of the recycled specimens is likely to be attributed to contamination level of oxide. (orig.)

2005-07-01

486

Assessment of effects of Fort St. Vrain HTGR primary coolant on Alloy 800. Final report  

Energy Technology Data Exchange (ETDEWEB)

A comprehensive review was conducted of primary helium coolant chemistry data, based on current and past operating histories of helium-cooled, high-temperature reactors (HTGRs), including the Fort St. Vrain (FSV) HTGR. A reference observed FSV reactor coolant environment was identified. Further, a slightly drier expected FSV coolant chemistry was predicted for reactor operation at 100% of full power. The expected environment was compared with helium test environments used in the US, United Kingdom, Germany, France, and Japan. Based on a comprehensive review and analysis of mechanical property data reported for Alloy 800 tested in controlled-impurity helium environments (and in air when appropriate for comparison), an assessment was made of the effect of FSV expected helium chemistry on material properties of alloy 800, with emphasis on design properties of the Alloy 800 material utilized in the FSV steam generators.

1982-08-01

487

Assessment of effects of Fort St. Vrain HTGR primary coolant on Alloy 800. Final report  

International Nuclear Information System (INIS)

A comprehensive review was conducted of primary helium coolant chemistry data, based on current and past operating histories of helium-cooled, high-temperature reactors (HTGRs), including the Fort St. Vrain (FSV) HTGR. A reference observed FSV reactor coolant environment was identified. Further, a slightly drier expected FSV coolant chemistry was predicted for reactor operation at 100% of full power. The expected environment was compared with helium test environments used in the US, United Kingdom, Germany, France, and Japan. Based on a comprehensive review and analysis of mechanical property data reported for Alloy 800 tested in controlled-impurity helium environments (and in air when appropriate for comparison), an assessment was made of the effect of FSV expected helium chemistry on material properties of alloy 800, with emphasis on design properties of the Alloy 800 material utilized in the FSV steam generators.

488

Application of alloy 800 in PWRs  

International Nuclear Information System (INIS)

Alloy 800 has been used by Siemens since 1968 and is now used by KWU for U-tubed steam generators in PWR's. The particular grade of alloy 800 that is used is within the ASTM-Specification B 163, but there have been modifications in composition to improve the corrosion resistance. First the permitted upper limit of carbon was reduced to 0.04% and was then further reduced to 0.03% and a stabilisation ratio of Ti : C >= 12 and Ti : C + N >= 8 was specified. The minimum permitted chromium and nickel levels were increased to 20% and 32% respectively. The maximum permitted levels of other elements or impurities were reduced. At the final fabrication stage peening with glass beads on the outer surface was specified to introduce a compressive stress to depth greater than that allowed for production flaws. An account is given of the behaviour of the alloy in service in four power plants already in operation, and future ...

489

Analysis of the fatigue strength of welded joints produced by different techniques in materials of the type 'alloy 800'  

International Nuclear Information System (INIS)

The alloy type 'alloy 800' with its different variants is used for numerous components in high-temperature reactor (HTR) plants, e.g. for hot-gas conductors, the high-pressure part of steam generators, superheaters, steam collecting vessels and live steam conductors. This study deals with the evaluation of creep rupture tests on 28 welded joints of alloy 800 with an accumulated test duration of 410 years, with the objective to obtain quantitative information on a possible loss of strength in comparison with the unwelded material. The longest test period of an individual test amounted to 98,000 h and the analyzed test temperature range lay between 550"0 and 1000"0C. (orig./MM).

1988-11-25

490

Analysis of the creep strain-time behavior of alloy 800  

Energy Technology Data Exchange (ETDEWEB)

The high-nickel austenitic alloy 800 (in both the mill-annealed and the solution-treated grades) has several attractive properties that make it a good candidate for service attractive properties that make it a good candidate for service at elevated temperatures in corrosive environments. One such property is creep resistance. This report analyzes the elevated-temperature creep behavior of the mill-annealed grade, generally referred to simply as alloy 800. (The solution-treated grade is known as alloy 800H). Available data over the temperature range from 538 to 760/sup 0/C were collected and evaluated to yield mathematically approximations for creep-rupture and strain-time behavior for use in design calculations. However, the creep behavior of this material is extremely complex, and the analysis presented here contains substantial uncertainties. All results in this report should be considered preliminary because of limited ...

1983-05-01

491

Amorphization of Zr_6_0Al_1_5Ni_2_5 surface layers by laser processing for corrosion resistance  

International Nuclear Information System (INIS)

It is generally known that a number of metallic glasses have excellent corrosion resistance in a variety of chemically hostile environments. Consequently, the use of laser cladding to coat a massive crystalline material such as aluminium with a layer of a metallic glass has obvious advantages. In this paper, the authors will show that the formation of a predominantly amorphous layer of Zr_6_0Al_1_5NI_2_5 alloy by laser processing is possible, if the obstacles to amorphization are overcome. In addition, evidence of the excellent corrosion resistance of this alloy in a NaCl solution will be given. A comparative study of the corrosion behavior of this amorphous alloy with pure aluminium and Al-Cr alloy will be done, in order to complete previous studies of laser processed coatings of aluminum substrates.

492

Alpha/Beta Heat Treatment of a Titanium Alloy with a Non ...  

Science.gov (United States)

... transformed at 705°C. The cooling rate and temperature dependence of matrix decomposition for Ti6242 was thus similar to that for Ti64 x [9]. ...

2006-08-01

493

Alloying element diffusion in alloy 800 H (UNS N08810) and alloy 617 (UNS N06617)  

Energy Technology Data Exchange (ETDEWEB)

Samples of alloy 800 H (LJNS N08810) and alloy 617 (UNS N06617) were oxidized in a simulated process gas atmosphere. The principal elements of the gaseous environment were 50% H{sub 2}O, 35% H{sub 2} and 5% of CO{sub 2}, CO, and CH{sub 4}, respectively. The experiments were carried out at temperatures from 850 C to 950 C for exposures ranging from 600 to 5,000 hours. After the exposure, the alloy surfaces showed compact oxide layers, which resulted in a depleted zone of oxidizing elements in the substrate layer. Using Electron Probe Microanalysis (EPMA), concentration profiles and the extension of the depleted zone were measured. Calculated theoretical profiles were then fitted to the EPMA-measured profiles, using Fick`s second law of diffusion and resolved by a finite difference method and diffusion coefficients as fitting parameters. The diffusion coefficients for chromium may be represented as D = Do exp.(-Q/RT) with the ...

1996-10-01

494

Alloy 800 welding experience at UKAEA Springfields  

International Nuclear Information System (INIS)

Investigatins into the welding of alloy 800 at the Reactor Fuel Element Laboratories, Springfields, commenced about three years ago following an extended development programme on tube to tube plate welding of low alloy and stainless steels for the Prototype Fast Reactor. The techniques and approach developed for critical fuel element welding applications had proved equally suitable for the precision welding requirements on the much heavier sections of heat exchangers. It had been demonstrated that the same control of weld quality and profile could be achieved with consistency and the permissible range of critical parameters could be readily defined. Because of this, development work was continued to include other materials, such as alloy 800, which might be of potential use. The tungsten inert gas (T.I.G.) arc welding process is used, and the equipment, including the control system, is described. Tube to tube-plate welding, ...

496

A probabilistic approach to the estimation of lifetime distribution of Alloy 800 SG tubing  

Energy Technology Data Exchange (ETDEWEB)

Alloy 800 has been used for steam generator (SG) tubing for more than 30 years, primarily in CANDU reactors and in reactors in Germany. Extensive laboratory testing and in-service experience suggest that the Alloy 800 tubing has excellent resistance to corrosion-related degradation under specified and appropriate operating conditions. In planning refurbishment of CANDU stations, a key concern is the longevity of existing SGs up to the 60 year lifetime of the refurbished plant. The paper reviews an existing methodology based on the concept of the improvement factor, and estimates it based on experimental data specific to CANDU operating conditions. The paper presents a more advanced probabilistic approach to estimate the degradation free lifetime distribution of Alloy 800 tubing, which is used to quantify the probability of degradation during the service life and to evaluate the impact of potential occurrences of degradation ...

2008-07-01

497

A probabilistic approach to the estimation of lifetime distribution of Alloy 800 SG tubing  

International Nuclear Information System (INIS)

Alloy 800 has been used for steam generator (SG) tubing for more than 30 years, primarily in CANDU reactors and in reactors in Germany. Extensive laboratory testing and in-service experience suggest that the Alloy 800 tubing has excellent resistance to corrosion-related degradation under specified and appropriate operating conditions. In planning refurbishment of CANDU stations, a key concern is the longevity of existing SGs up to the 60 year lifetime of the refurbished plant. The paper reviews an existing methodology based on the concept of the improvement factor, and estimates it based on experimental data specific to CANDU operating conditions. The paper presents a more advanced probabilistic approach to estimate the degradation free lifetime distribution of Alloy 800 tubing, which is used to quantify the probability of degradation during the service life and to evaluate the impact of potential occurrences of degradation ...

2008-06-01

499

8 - NASA Technical Reports Server  

Science.gov (United States)

Palladium silicides (Pd(x)Si) formed at a broadened interface after annealing, but a significant layer of alloy film is still free of silicon and carbon. ...