Showing papers on "Zirconium alloy published in 1972"
TL;DR: In this paper, a martensitic mechanism is proposed for the formation of twinned hydride and twinned and untwinned γ-hydrides, and its implications for the precipitation behaviour of hydrides in the can of a reactor fuel element are outlined.
189 citations
TL;DR: In this article, the diffusion coefficient of hydrogen in zirconium, Zircaloy-2 and Zirca-4 was determined in the temperature range, 275 °C to 700 °C.
152 citations
68 citations
TL;DR: In this paper, the fractography of zirconium and cesium alloy specimens cracked in a number of aggressive environments, such as methanol-hydrochloric acid solutions, although intergranular attack on unstressed specimens also occurs, the application of external stress causes a change to transgranular cracking.
Abstract: The fractography of zirconium and zirconium alloy specimens cracked in a number of aggressive environments has been studied. In methanol-iodine at room temperature, fractures are completely intergranular, but penetration occurs even in the absence of applied stresses. In methanol-hydrochloric acid solutions, although intergranular attack on unstressed specimens also occurs, the application of external stress causes a change to transgranular cracking. When exposed in air at 300 to 450 C (572 to 842 F) with coatings of chloride salts or immersed in a fused nitrate-iodide salt mixture, cracking of stressed specimens is predominantly transgranular, whereas in fused nitrate-chloride and .nitrate-bromide salts at 300 to 450 C, the penetration is intergranular and occurs even on unstressed specimens with gross internal oxidation. Transgranular fractures can also be caused during dynamic bend tests in mercury and cesium. The transgranular fractures in methanol-hydrochloric acid; hot and fused salts; and ...
52 citations
TL;DR: The deformation and fracture of Zircaloy-4 and pure zirconium sheets having strong (0002) textures were studied under plane-strain compression at temperatures from 20° to 800°C as discussed by the authors.
51 citations
01 Feb 1972-Metallurgical and Materials Transactions B-process Metallurgy and Materials Processing Science
TL;DR: In this paper, the Bureau of Mines has produced ductile zirconium dendrites at 800°C in an electrolyte containing NaCl-NaF-ZrCl4.
Abstract: The Bureau of Mines has produced ductile zirconium dendrites at 800°C in an electrolyte containing NaCl-NaF-ZrCl4. Sublimed zirconium tetrachloride was fed into NaCl containing a slight excess of NaF above that required to complex 2 pct Zr as Na2ZrF6. The chlorine gas generated at the graphite anode during electrolysis was confined in and vented out of the cell through a high-density graphite tube into a scrubbing solution of NaOH. At a cathode current density of 300 amp per sq ft, the zirconium metal produced was 95 pct +200 mesh size. The average anode and cathode current efficiencies were 86 and 96 pct. The metal product in the form of arc-melted buttons has a hardness ranging from 130 to 170 Bhn and can be cold-rolled into 15-mil thick strips without intermediate annealing.
37 citations
TL;DR: In this article, the authors derived the anisotropic factors which apply to creep deformation at relatively low stresses, temperatures of 260° to 300°C and fast neutron flux from 0.6 × 1013 to 3.5× 1013 n/cm2s (> 1 MeV).
36 citations
TL;DR: In this paper, the effects of various alloying elements and strengthening methods in zirconium alloys have been assessed and it has been shown that alloys with adequate strengtl1 for use as pressure tube material at temperatures above 400°C can be developed.
33 citations
TL;DR: The conditions for the reaction of zirconium sponge with methylene dichloride and with chlorine in the deposition of ZIRconium carbide-carbon composites have been examined in this paper.
Abstract: The conditions for the reaction of zirconium sponge (a) with methylene dichloride and (b) with chlorine in the deposition of zirconium carbide-carbon composites have been examined. Hydrogen must be present in the process involving methylene dichloride. In the chlorine process deposition is from zirconium tetrachloride, which is continuously generated by reaction of the sponge with chlorine and a hydrocarbon, methane being used in this work. Appreciable deposition of composite occurs above 1000 °C in both processes. The mechanism of deposition is briefly discussed.
29 citations
TL;DR: In this paper, a relation between texture and the mechanical anisotropy of zirconium is developed, and rules are suggested for softening and hardening caused by texture change.
TL;DR: Zirconium-based alloys with small additions of tin, molybdenum, niobium and aluminum are being developed as candidate materials for high-strength pressure tubes in advanced CANDU reactors as mentioned in this paper.
Patent•
12 May 1972
TL;DR: In this article, the authors describe the work of ZIRCONIUM Alloy and METAL Alloy, which is defined as "the work of a zirconium in movable contact with another METAL" in the context of a WATERSOLUBLE POLYGLYCOL.
Abstract: 1. IN THE WORKING OF ZIRCONIUM OF A ZIRCONIUM ALLOY WHICH IS PREDOMINANTLY ZIRCONIUM IN MOVABLE CONTACT WITH ANOTHER METAL, THE IMPROVEMENT WHICH COMPRISES LUBRICATING THE CONTACTING SURFACES OF SAID ZIRCONIUM OR ALLOY AND METAL WITH LUBRICATING AMOUNTS OF A WATERSOLUBLE POLYGLYCOL HAVING A MOLECULAR WEIGHT OF AT LEAST ABOUT 400.
01 Jan 1972
TL;DR: In this article, the authors proposed a method to minimize the chance of a fuel failure by careful attention to design and development, choice of materials and method of operation, but there is always a finite chance of fuel failure.
TL;DR: In this paper, slow-bend testing of various samples of zirconium and zircaloy-2, hydrided to different levels up to 1000 ppm, has revealed a transition temperature below which unstable crack propagation occurs.
TL;DR: Internal friction studies on dilute zirconium alloys containing the interstitial impurities oxygen and nitrogen have indicated that the internal friction is caused by an interaction of substitutional and interstitial atoms as mentioned in this paper.
TL;DR: In this paper, the effects of thermal and stress cycles on the orientation of hydride, simulating reactor operation, were investigated, and the effect of stress was not significant up to 1...
TL;DR: In this article, the first corrosion and hydrogen pickup by zircaloy in water and steam was described, and the principal alloys used or considered were discussed, with the main emphasis on hydrogen pickup in-pile.
TL;DR: In this paper, the basic role played by these alloying elements is not well understood, but it has been possible to make correlations between observed surface phenomena (of both impurity and alloy species) and previously established mechanical properties, such as a strain rate sensitivity around 300 °C in the zircaloys, and also chemical properties such as the build-up of an oxide layer above 300 Ã c in these same zirconium alloys.
Abstract: Several metals used in the nuclear field are found to be lacking in one or more respects when these metals are employed in their pure or unalloyed state. For a variety of reasons, minor alloying additions are often added to these pure metals. However, the basic role played by these alloying elements is not well understood. By utilizing the technique of Auger electron spectroscopy on zircaloy-2 and zircaloy-4, it has been possible to make correlations between observed surface phenomena (of both impurity and alloy species) and previously established mechanical properties, such as a strain rate sensitivity around 300 °C in the zircaloys, and also chemical properties such as the build-up of an oxide layer above 300 °C in these same zirconium alloys.
01 Jan 1972
TL;DR: In this paper, it was shown that secondary in-reactor creep of cold-worked zirconium alloys is texture-dependent, for stresses larger than 15 000 psi.
Patent•
30 Nov 1972
TL;DR: In this article, the surface treatment of zirconium-base cladding materials for fuel elements or other components for nuclear reactors is described, wherein the treatment includes pickling said cladding material in a fluoride-containing bath, and thereafter applying a protective coating through oxidation to the pickled claddings material whereby the fluoridecontaining contaminents which remain on the surface of the cladding during pickling are removed or rendered harmless by anodic oxidation.
Abstract: A process for the surface treatment of zirconium-base cladding materials for fuel elements or other components for nuclear reactors, wherein the treatment includes pickling said cladding material in a fluoride-containing bath, and thereafter applying a protective coating through oxidation to the pickled cladding material whereby the fluoride-containing contaminents which remain on the surface of the cladding material during pickling are removed or rendered harmless by anodic oxidation.
01 Jan 1972-Metallurgical and Materials Transactions B-process Metallurgy and Materials Processing Science
TL;DR: In this paper, the effects of adding silver, substituting other elements for chromium, increasing zinc, or varying the copper content on the tensile properties and resistance to stress-corrosion cracking of 7075-type alloys were investigated.
Abstract: The separate and combined effects of adding silver, substituting other elements for chromium, increasing zinc, or varying the copper content on the tensile properties and resistance to stress-corrosion cracking of 7075-type alloys were investigated. Adding silver produced no increase in strength and marginal increases in the resistance to stress-corrosion cracking. Substituting either zirconium or manganese for chromium increased strength and decreased the resistance to stress-corrosion cracking after a given precipitation heat treatment; at equal strength levels, the resistances to stress-corrosion cracking of the chromium-free alloys below 3 in. (76 mm) thickness were comparable to those of 7075. Increasing zinc increased the resistance to stress-corrosion cracking but increased quench sensitivity. Decreasing copper decreased the resistance to stress-corrosion cracking in the atmosphere. Increasing copper in chromium-free alloys provided the best combination of strength and resistance to stress-corrosion cracking. Longer atmospheric exposures are needed to firmly establish the stress-corrosion resistance.
01 Jan 1972-Metallurgical and Materials Transactions B-process Metallurgy and Materials Processing Science
TL;DR: In this paper, the fatigue behavior of 20% hydrided 20% cold-worked zircaloy-2 reactor pressure-vessel tubing has been studied for fluctuating tension at room-temperature and 300 °C and for reversed torsion at room temperature.
TL;DR: The diffusion of nickel and tin in alpha and beta zircaloy-2 has been studied by the residual activity technique in the temperature range 650-1250 °C as discussed by the authors.