Cu-Zn-Al shape memory alloys may offer good thermomechanical properties for industrial applications. However, it is important to control transformation temperatures,the aging and the fatigue behaviour.
We compare in this paper the effects of two thermomechanical treatments on industrial springs:
“Direct” treatment consists in homogenization in β phase, annealing and training.
“Inverse” treatment consists in homogenization in β phase, training and annealing.
A correlation between electron microscopy observations and D.S.C. experiments shows that heterogeneous ordered state (β+y2+β3) in Cu25%wtZn9%wtAl is an essential parameter influencing mechanical hysteresis.