Ni—Ti形状记忆合金在使用过程中经受着相变热循环或应力加相变热循环的作用;已发现热循环导致产生高密度的位错,并且伴随着Ms点的降低。因而,这些位错的性质、产生的机制及其在马氏体转变中的作用成为人们关切的研究课题。本工作用透射电子显微术详细地研究了50.5at％Ni—Ti合金热循环过程中产生的位错的组态和性质。用“g· Ni-Ti shape memory alloys are subject to phase change thermal cycling or stress plus phase change thermal cycling during use; thermal cycling has been found to result in high density dislocations accompanied by a reduction in the Ms point. Therefore, the nature of these dislocations, the resulting mechanism and its role in the transformation of martensite has become a research topic of concern. In this work, the configuration and properties of dislocations generated during the thermal cycling of a 50.5 at% Ni-Ti alloy were investigated in detail by transmission electron microscopy. With "g ·