ACOUSTIC EMISSION DURING MARTENSITIC TRANSFORMATION OF Cu-Zn-Al

The characteristic transformation temperatures of small samples of a CuZnAl alloy were determined by resistivity measurements. Ring-down counting measurements of acoustic emission during tFmperature cycling of t hese samples show distinctive maxima occurring near Ms(T 0). Counting rates depend strongly on mechanical/thermal sample history but are always proportional to temperature variation rate. Detailed event recordings reveal burst-like signals of widely fluctuating amplitudes generated by source processes of very short duration. Their characteristics are little affected by different rates of temperature variation.