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Cu70Zn26Al4合金中存在马氏体转变,高压电镜(1000kV)和分析电镜的观察表明,在室温下的平衡母相为β’相(DO_3型),有部份淬火马氏体、表面马氏体存在,还有少量的γ相。在相变过程内,样品中有微裂纹产生和扩展;在冷却实验中,马氏体以母相的(101)面为基面,新相结构为M12R+2H型,没有择优取向问题。在应力诱发马氏体相变中,马氏体以母相的(110)面为基面,新相结构为M18R,存在择优取向问题。在冷却实验中和应力诱发马氏体相变中,都存在β相的预转变,预马氏体的9R和12H衍射极大。在应力诱发马氏体相变中,预马氏体的出现与否与应力施加的速率有关。
The martensitic transformation existed in Cu70Zn26Al4 alloy. The observation of high voltage electron microscope (1000kV) and SEM showed that the equilibrium mother phase was β ’phase (DO_3) at room temperature, some quenched martensite and surface martensite existed , There is a small amount of γ phase. During the phase transition, micro-cracks were formed and extended in the sample. In the cooling experiment, the martensite was dominated by the (101) plane of the parent phase and the new phase was M12R + 2H. There was no preferential orientation. In the stress-induced martensitic transformation, the martensite is dominated by the (110) plane of the parent phase and the new phase structure is M18R, which presents the problem of preferential orientation. In the cooling experiment and stress-induced martensitic transformation, there is pre-transformation of β phase, pre-martensite 9R and 12H diffraction maximum. In stress-induced martensitic transformation, the presence or absence of pre-martensite is related to the rate of stress application.