Accession Number : AD0282836

Title :   A STUDY OF QUENCH HARDENING IN PLATINUM AND GOLD

Corporate Author : AERONAUTICAL SYSTEMS DIV WRIGHT-PATTERSON AFB OHIO

Personal Author(s) : GEGEL,HAROLD LOUIS

Report Date : MAY 1962

Pagination or Media Count : 1

Abstract : Vacancy complexes were formed during the quenching period when the average quenching speed was less than 10 to the 5th power degree C/sec. The binding energy for divacancies in Au was estimated to be approximately 0.28 ev. The influence of increased quenching speeds is to increase the temperature recovery range for isochronal recovery. Similarly, fast quenching rates caused an incubation period in the isothermal aging experiments for Au. No incubation period was observed for Pt. The incubation period is attributed to the time necessary to develop vacancy complexes which have the appropriate geometry to influence the yield strength. The activation energy for recovery in the quench-hardened Pt was determined to be 1.43 ev, which is less than the activa ion energy for self-diffusion. It was observed to be approximately equal to the sum of the constriction energies for screw and edge dislocations. The activation energy for Au is greater than that for self-diffusion. Two distinct hardening mechanisms exist for Pt and Au when the values of the activation energy for recovery are taken into account. The hardening mechanism for Au is thought to be due to the inter ction of dislocations with extended sessile dislocations. (Author)

Descriptors :   *GOLD, *PLATINUM, AGING (PHYSIOLOGY), COOLING, CRYSTAL STRUCTURE, CRYSTALS, DEFORMATION, HARDENING, HEAT TREATMENT, MECHANICAL PROPERTIES, PROCESSING, RECOVERY, TEMPERATURE, TENSILE PROPERTIES

Distribution Statement : APPROVED FOR PUBLIC RELEASE