Stability of the High Temperature Beta Phase in Beryllium and Beryllium Alloys (Final Technical Report to the United States Atomic Energy Commission for the Period July 1, 1960 Through June 30, 1961)

Technical Report · Mon Sep 11 04:00:00 EDT 1961

DOI:https://doi.org/10.2172/4833887· OSTI ID:4833887

Pickett, J. J. ^[1]; Levine, E. D. ^[1]; Nowak, W. B. ^[1]

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1. Nuclear Metals, Inc., Concord, MA (United States)

The discovery of a high-temperature phase in beryllium has opened a new field of study in beryllium metallurgy. Studies in this field have been carried out over the past year. Differential thermal analysis (DTA) to determine equilibrium phase boundaries has been applied to alloys of beryllium in each of the following systems: barium, cerium, cobalt, copper, lanthanum, manganese, platinum, silver, nickel-cobalt, nickel-iron, nickel-copper, nickel-cobalt-iron, and nickel-cobalt-manganese. The boundaries of the beta beryllium regions in the systems beryllium-cobalt and beryllium-copper have been fairly well established; the remaining systems require further study using additional test methods. The beryllium-nickel system, studied previously, and the beryllium-cobalt and beryllium-copper systems enlarge the beta field and lower the beta-to-alpha transus temperature, thus making these systems suitable for further study of the beta phase. A correlation was found between the beta-alpha upper solvus transition temperatures and electron-to-atom ratios for alloys of beryllium with cobalt, copper, iron and nickel. Application of this relationship to ternary and quaternary alloys met with some success. Lowering of the beta-alpha transformation temperature by quenching from the beta phase was attempted on beryllium-cobalt and beryllium nickel alloys using a modified Greninger helium-gas quenching apparatus. Initial cooling rates up to 60,000°C/sec have been observed with the transformation temperature lowered to 242°C. Suppression of the alpha phase, as measured by X-ray diffraction, has not been observed. On the basis of a few tests, the beta phase structure appears to be more ductile than the alpha phase structure at elevated temperature. A Be-8 ^a/o nickel alloy exhibited 20 percent reduction in area in tensile tests at 1070°C (at which temperature the alloy is mostly beta). Unalloyed beryllium exhibited zero reduction in area at this temperature.

• Research Organization: Nuclear Metals, Inc., Concord, MA (United States)
• Sponsoring Organization: US Atomic Energy Commission (AEC)
• NSA Number: NSA-16-002180
• OSTI ID: 4833887
• Report Number(s): NMI--1252
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALLOTROPY
BARIUM COMPOUNDS
BERYLLIUM
BERYLLIUM ALLOYS
CERIUM ALLOYS
COBALT ALLOYS
COPPER ALLOYS
DTA
DUCTILITY
EXPANSION
HIGH TEMPERATURE
IRON ALLOYS
LANTHANUM ALLOYS
MANGANESE ALLOYS
NICKEL ALLOYS
PHASE DIAGRAMS
SILVER ALLOYS
TEMPERATURE