摘要
通过SEM分析 ,研究了时效后不同成分Fe Mn Si Cr Ni C系记忆合金形状记忆效应和微观组织。在 112 3K时效时 ,超低碳合金 1的形状回复率随时效时间的增加一直呈直线上升的趋势。含碳 0 .18%合金 2的形状回复率随时效时间的增加而增加 ,在 3 0 0min达到最大值后将随时间的进一步增加而缓慢下降。SEM分析发现在合金 2的晶界和晶内析出富铬 ,富锰和富硅的合金碳化物 ,而合金 1仅在晶界有第二相析出 ,且第二相成分不同于合金 2中的。合金 2中第二相粒子的长大速度显著高于合金 1中第二相粒子的长大速度 ,且数量也多得多 ;通过时效强化奥氏体基体 ,可显著提高合金的形状记忆效应。
The shape memory effect and the microstructure in Fe Mn Si Cr Ni C shape memory alloys after aging have been studied by SEM analysis. The shape recovery ratio in the alloy 1 with ultralow carbon contnet increases with increasing the aging time when aged at 1123K. The shape recovery ratio in alloy 2 with 0.18% carbon content increases with increasing aging time when the aging time is less than 300min, and a maximum value can be obtained at 300min. When greater than 300min, it will decrease gradually. The SEM analysis shows that the second phase particles precipitated both in grain boundary and inside grain of alloy 2, and these particles were carbides rich in chromium, manganese and silicon. While the second phase particles in alloy 1 precipitated only in grain boundary,whose composition is also different from that of alloy 2. The amount of the second phase particles in alloy 2 is much more than that in alloy 1. What is more, the growth velocity of the second phase particles in alloy 2 is also much faster than that in alloy 1. The shape memory effect in the tested alloy can be improved appreciably through strengthening austenite matrix by aging.
出处
《功能材料》
EI
CAS
CSCD
北大核心
2002年第6期624-625,共2页
Journal of Functional Materials
基金
四川省科委重点资助项目 (川科委计 [1 9999] 9)
