摘要
利用金相显微镜、透射电镜、电子探针分析观察Ag—0.5Ce(wt％)合金试样内的晶粒和第二相颗粒的尺寸、分布及形貌,测定了高温处理后的第二相颗粒的结构。结果表明:在700℃以下,晶粒生长比较缓慢;在700℃以上,晶粒发生快速的不均匀生长。在合金表层由于CeO_2的形成阻止表层晶粒长大。在515℃以下,第二相颗粒有因Ce由α-Ag中析出而引起的小的长大趋势;在515℃以上,发生Ag_4Ce相的消溶,引起第二相粒子尺寸及体积分数的下降。
The size, distribution and morphology of the grain and second phase particles in Ag-0.5wt.% Ce alloy have been examined using the metallographic microscope, transmission electron microscope and electron probe. The structure of second phase particles after annealling at high temperature is determined. The results show that growth of grains at temperature below 700℃ is relatively slow, and above 700℃, the growth is rather quick and heterogeneous. The growth of grains in the surface zone is constrained by the formation of CeO_2 in the area. When temperature is lower than 515℃, the second phase particles grow slowly because of the precipitation of the cerium from α-Ag. On the contrary, when temperature is above 515℃, the dissolution process of Ag_4Ce occurs and results in the reduce of the size and volume fraction of the second phase particles.
出处
《贵金属》
CAS
CSCD
北大核心
1992年第2期18-28,共11页
Precious Metals
基金
国家自然科学基金
关键词
银基合金
显微结构
高温试验
Silver-base alloys, Cerium additionm Microstructure, High temperature test
