【作者】 李宁； 文玉华； 胥永刚；

【Author】 LI Ning;WEN Yu-hua;XU Yong-gang Department of Materials Shaping and Controlling Engineering, Sichuan University Chengdu, 610065,China

【机构】 四川大学材料成形与控制工程系；

【摘要】 本文研究了热机械循环训练对Fe-Mn-Si-Cr-Ni-C系形状记忆合金形状记忆效应的影响。结果表明:对于不同碳含量的3种合金,只要中间退火温度选择适当,热机械循环训练都可显著提高合金的形状记忆效应。合金的最佳中间退火温度随碳含量的增加而升高。合碳最低(<0.02%)合金的最佳中间退火温度为550℃,而含碳0.18%合金的最佳退火温度高达1050℃。经TEM分析,发现对于低含碳量(≤0.12%)的两种合金,热机械循环训练提高合金形状记忆效应的机制是层错增加机制;而对于碳含量0.18%的合金3,其机制是第二相的析出,基体强化机制。且基体强化机制的效果大于层错增加的效果。更多还原

【Abstract】 The effect of thermal-mechanical cycle on shape memory effect of Fe-Mn-Si-Cr-Ni-C shape memory alloyshave been studied. The results show that the shape recovery ratio in alloys with different carbon content can beimproved markedly by the therma1-mechanical cycle, when the middle annealing temperature was selected properly.The optimal middle annealing temperature increases with the increase of the carbon content. The optimal middleannealing temperature of the alloy with the carbon content less than 0.02% was 550℃, while that of the alloy with0. 18% carbon l050℃. The improvement of shape memory effect in the alloys with the carbon content less than 0. 12%by the thermal-mechanical cycle is due to the increase of the stack fault amount through TEM analysis, While that inthe alloy with 0.18% carbon is due to precipitation of the second phase partic1es, which strengthens the austenitematrix. The effect of Strengthening matrix is greater than that of the increase of the stack fault amount.更多还原