Abstract:The deformation behaviour of Cu-Zn-Al alloys and its effect on the transformation hysteresis were studied.It is shown that the critical stress for martensite boundary movement and the intrinsic transformation hysteresis of the alloys can be raised by increasing Al content and adding Mn element.For Cu-10.2 Al-4.9 Mn-4.6 Zn-0.3 Zr alloy,its transformation hysteresis increases more rapidly and its reversible martensite amount decreases more slowly as the strain increases.The main reason is that the increasing of Al content and adding of Mn element can strengthen the alloy and make the grains become more fine,which can improve the deformation resistance,reduce the irreversible defaults and make the energy for changing the martensite configuration increase.The wide transformation hysteresis effect of Cu-10.2 Al-4.9 Mn-4.6 Zn-0.3 Zr alloy were discussed as well, according to structure changes during deformation.

Key words: shape memory alloy Cu-Zn-Al alloy martensite transformation boundary movement transformation hysteresis