Accession Number : AD0780799

Title :   Investigation of Microquenched Magnesium ZK60A Alloy.

Descriptive Note : Final rept.,

Corporate Author : ARMY MATERIALS AND MECHANICS RESEARCH CENTER WATERTOWN MASS

Personal Author(s) : Isserow,Saul

Report Date : APR 1974

Pagination or Media Count : 20

Abstract : The substantial improvement of tensile behavior and impact resistance of magnesium ZK60A alloy by microquenching was confirmed. Metallographic examination showed that much of the strengthening, observed to approach 20 ksi, is attributable to the unusually fine grain size in rods extruded from microquenched powder. The powder itself is not unusually fine-grained but seems to embody features that make the consolidated material highly responsive to cold working, recrystallization, and aging. The grain size of the consolidated rods can, with a reasonable value for the Hall-Petch constant, be shown to account for the strength increment relative to ordinary commercial material obtained by casting and working. The powder-derived material also contains a fine intermetallic precipitate. The powder-derived material showed a fracture mode in both tension and impact tests that strongly involves separation or debonding of parallel strands. This fracture occurs in steps, is slower than the ordinary shear fracture, and absorbs much more energy. (Modified author abstract)

Descriptors :   *Magnesium alloys, *Powder metallurgy, Quenching, Fabrication, Zinc alloys, Zirconium alloys, Impact tests, Tensile properties, Fracture(Mechanics), Grain size

Subject Categories : Metallurgy and Metallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE