Effects of cavitation on grain structure and phase transformation of CuZnAl shape memory alloy

Abstract

ABSTRACT The present study aims to elucidate the effects of cavitation on the CuZnAl shape memory alloy. Cavitation was produced by the propagation of ultrasonic waves in deionized water. Influences of the exposure time and the standoff distance were considered. The mass loss of the specimen was measured. The specimen surfaces were observed using microscopes. Grain orientations were detected using the X-ray diffraction technique. The specific heat capacity was measured using a differential scanning calorimeter. The highest cavitation aggressivity is attained at the standoff distance of 0.7 mm. As the exposure time increases, both the mass loss and surface roughness are enhanced. The cavitation impact leads to the refinement of grains and diversification of grain orientations. Furthermore, the austenite start temperature is reduced and the stability of thermoelastic martensite attenuates due to cavitation. The improvement of the shape memory performance of the CuZnAl shape memory alloy is evidenced.