Volume 22, Issue 6 (November 1994)
Determination of Softening Kinetics in a Material by Measuring the Evolution of Hot Flow Stress
A new technique for estimating the time and temperature-dependent softening response of a deformed material is proposed. The hot flow stress is measured at various intervals in a quasistatic softening experiment to determinse the kinetics of softening. A major advantage of the proposed technique is that a single specimen can be used to estimate the evolution of softening without having to cool and reheat the specimen for each measurement. High resolution strain measurement apparatus is used in the experiments, as minimizing strain is a critical requirement in property performing the measurement. Test control requires optimal performance from the servohydraulic system which must operate near its threshold for reliable information to be obtained. Experimental results indicate that age hardening response as well as recovery and recrystallization kinetics can be measured using this method.