摘要
本文采用一种精确测量形状记忆效应（ＳＭＥ）和观察不同时期显微组织的方法，研究了Ｃｕ－２６（ｗｔ）％Ｚｎ－４（ｗｔ）％Ａｌ合金，在８００℃淬火后重返母相区１３０℃、１５０℃和１７０℃时效的变化规律．实验结果表明，淬火马氏体进入母相区时效初期形状记忆回复率迅速升高，达到一个最大值后随时效时间而下降，显示出时效过程中马氏体稳定化效应的消除和贝氏体相变的发展这两种不同机制对ＳＭＥ所引起的相反效果，即马氏体稳定化的消除增强着ＳＭＥ而贝氏体相变的发生却恶化着ＳＭＥ．贝氏体在晶界的析出对ＳＭＥ已颇为有害，而当贝氏体在晶内形成时ＳＭＥ将激烈恶化．
Changes in shape memory effect (SME) after aging at 130, 150 and 170℃ at the parent state in a Cu-26% (wt) Zn-4% (wt)Al alloy quenched from 800℃ are studied by an exact measurement of SME and metallography. Experimental results show that the shape memory recovery rate remarkably increases at the early aging stage. However, after reaching a maximum value, SME decreases with the aging duration, which implies that two opposite factors with two different mechanisums affect the SME, i. e. the annihilation of the stabilization of the martensite improves the SME and the occurrence of the bainitic transformation deterionates the SME. A trace of bainite precipitating at the grain boundary will slightly harm the SME. As bainite forms within the grain, the SME will drastically decrease.
出处
《上海交通大学学报》
EI
CAS
CSCD
北大核心
1995年第5期68-72,共5页
Journal of Shanghai Jiaotong University
基金
国家自然科学基金
关键词
贝氏体相变
形状记忆效应
铜锌铝合金
aging at parent state, stabilization of martensite, bainitic transformation, shape memory effect
