研究了热机械训练次数对 Fe-Mn-Si 系形状记忆合金记忆效应的影响。结果表明,随着训练次数的增加,合金可回复应变先增加后降低,3次热机械训练后合金的回复率达到最高1.95%。微观结构分析表明,记忆效应在初始阶段升高的原因主要归结于热机械训练诱发马氏体择优取向,ε马氏体分布比较均匀,相互平行,交叉现象较少,多次(4次以后)训练回复率降低则主要是由于合金基体内部形成大量位错缠结,产生不可逆塑性变形所致。%Effect of the times of thermo-mechanical training on the shape memory of Fe-Mn-Si shape memory al-loy was studied in this paper.The results show that with the increase of the number of training,alloy strain re-covery rate rises to the highest 1.95% after three training sessions and then begins to decrease.Microstructure analysis showed that the rise of it in the initial stage could be attributed mainly to thermo-mechanical training, inducing martensitic preferred orientation and resulting in a uniform distribution of martensite which was run-ning parallel with each other with few of crossover.While the decrease of the recovery rate was primarily due to the serious dislocation tangle forming inside the alloy matrix,which leads to irreversible plastic deformation.
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