NATURE OF STRAIN HARDENING IN POLYCRYSTALLINE INDIAN COMMERCIAL ALUMINUM

Abstract

A desniption of the constant-stress-creep testing unit and constant strain-rate tensile testing machine, designed and built in the Department is given. The nature of strain hardening in Indian commercial aluminum is investigated with the help of combined data on creep rests at 86°K and tensile tests in the temperature range 86' -473°K at two strain rates. The engineering tensile deformation aura are also presented The activation voliane ( 2 x 1021 cm3) and total activation energy (0.75 e V ) for the rate-controlling dislocation mechanism are estimated. The thermally activatednon-conservative motion ofjogs ieading to point defectproduction is discussed in the light of the present data.