摘要
本文主要研究了670℃时效不同时效时间对Fe-Ni基高强度低膨胀合金碳化物显微组织性能的影响。结果表明:670℃时效时,随着时效时间的延长,合金基体晶粒逐渐呈等轴化,并且有二次相以带状在小晶粒附近析出,时效3h硬度可达最大值。TEM和SAD结果表明,时效过程中,有多角状圆粒M6C,长片状M2C型两类富含Mo的碳化物析出,对合金有较明显的强化作用。时效初期,合金的膨胀系数逐渐增大,但是随着碳化物的析出,基体膨胀系数的减小,合金的膨胀系数有所下降。
The influence of aging treatment at 670℃ on the microstructure and property of Fe-Ni based high strength low thermal expansion alloy was investigated. The results show that the matrix grains of alloy aged at 670℃ became equiaxed gradually with second phases precipitated along small grain bands, since the aging treatment time prolonged. The microhardness of the alloy aged for 3h reached maximum. The results of TEM and SAD indicated that there were two kinds of carbides precipitated during the aging treatment. They were intergranular M6 C type carbide and lamellate M2C type carbide,which both rich in Mo. The coefficient of thermal expansion of alloy increased at the beginning of aging treatment. Rut it decreased with the precipitation of carbides, because of the reduction of coefficient of thermal expansion of matrix.
出处
《金属功能材料》
CAS
2007年第3期10-14,共5页
Metallic Functional Materials
基金
科技部科研院所研究开发专项资金(No.科05021050)
关键词
FE-NI合金
时效
显微组织
碳化物
线膨胀系数
Fe-Ni based alloy
aging treatment
microstructure
carbide
coefficient of thermal expansion
