铜基形状记忆合金时效过程中的原子有序态变化

CHANGES OF ATOMIC ORDER IN Cu-Al-Ni-Mn-Ti SHAPE MEMORY ALLOY DURING AGING

高温Ｘ射线衍射及原位电阻测量等实验结果表明，淬火态Ｃｕ—Ａｌ—Ｎｉ—Ｍｎ—Ｔｉ形状记忆合金在母相和马氏体状态时效过程中，原子有序态的演变及时效机制是不同的．在母相态时效，先发生ＤＯ_３再有序化，随后发生原子短程无序或偏聚并进而析出贝氏体或平衡相．在马氏体状态时效，ＤＯ_３长程有序度无显著变化，没发生类似在母相态的再有序化，主要是原子短程无序化．

The changes of atomic order state during aging of the parent phase and martensite in an as-quenched Cu-Al-Ni-Mn-Ti shape memory alloy were investigated by X-ray diffraction and in situ electrical resistivity measurements. It was shown that the aging mechanisms of the parent phase and martensite are different. During parent phase aging, DO_3 atomic reordering occurs, leading to an increase in the degree of long range order. During martensite aging, however, short range atomic disordering takes place, resulting in the stabilization of martensite.