摘要
研究了RE对Mg 8Zn 4Al 0 .3Mn铸造镁合金显微组织的影响。结果表明 :Mg 8Zn 4Al 0 .3Mn xRE铸造镁合金的显微组织主要由α(Mg)基体、φ(Al2 Mg5Zn2 )相、τ(Mg3 2 (Al,Zn) 49)相和Mg3 Al4 Zn2 RE相组成。随RE加入量的增加 ,合金晶界上三元相的形态由半连续网状改变为颗粒状 ,三元相的分布逐渐变得弥散而均匀。晶界上针状或棒状Mg3 Al4 Zn2 RE相的量也随着RE加入量的增加而增加。加入 1.5 %的RE可显著细化合金的铸态组织 ,晶粒大小由 12 0～ 130 μm减小到 40～ 5 0 μm。合金的显微硬度值随着RE加入量的增加而增加。
The effects of Al5TiB addition on aging process of Mg-8Zn-4Al-0.3Mn alloys have been studied. The results show that the aging precipitation process of Mg-8Zn-4Al-0.3Mn alloy without Al5TiB addition is: supersaturated magnesium solid solution→small and dispersed precipitation phases→recrystallization soften and aggregation growth of precipitation phases, and that of magnesium alloys with Al5TiB addition is: supersaturated magnesium solid solution→small and dispersed precipitation phases→aggregation growth of precipitation phases. After solid solution treatment, comparison with 1~# alloy without Al5TiB addition, microhardness values of alloy 2~#, 3~# and 4~# increase by 2.8%, 6.8% and 9.1%, respectively and after artificial aging, those of alloy 2~#, 3~# and 4~# increase by 9%, 11.2% and 5.2%, respectively. Precipitation formation activation energy of alloy increases firstly and then decreases with increasing content of Ti element.
出处
《中国有色金属学报》
EI
CAS
CSCD
北大核心
2003年第3期616-621,共6页
The Chinese Journal of Nonferrous Metals
关键词
镁合金
显微组织
稀土
显微硬度
Mg-8Zn-4Al-0.3Mn alloy
Al5TiB
solid solution treatment
aging process
