摘要
研究了Mg-(1%~3%)Sm(质量分数)合金在多种状态下的显微组织和力学性能.采用光学金相分析(OM),扫描电子显微分析(SEM),X射线衍射分析(XRD)等多种分析和测试手段,系统研究了挤压工艺及热处理(固溶处理、时效处理)对Mg-Sm系合金显微组织和力学性能的影响.结果显示,合金的铸态组织由α-Mg基体和Mg41Sm5组成.合金经热挤压加工后,Mg41Sm5相沿挤压方向呈纤维或颗粒状分布.在420℃挤压时,试样内发生了动态再结晶,致使挤压后合金的强度和塑性得到大幅度改善.固溶以及时效处理后,合金的性能比铸态有较大提高;而采用挤压后的直接时效(T5)处理,可获得良好的综合力学性能.因此,Sm可以考虑作为强化变形镁合金的添加元素.
Three binary Mg- ( 1% to 3 % ) Sm alloys were prepared and their microstructure and mechanical properties were investigated. The effects of extrusion and heat treatment on the microstructure and mechanical properties of Mg-Sm binary alloys were investigated by using an optical microscope (OM), a scanning electron microscope (SEM), and an X-ray diffract meter (XRD). The results show that the microstructure of the alloys prepared as-cast consists of an a-Mg matrix and Mg41 Sm5 intermetallic compound. After the hot-extrusion, the Mg41 Sm5 phase shows fibrous and granular morphology along the extrusion direction. Dynamic recrystallization occurs during extrusion at 420℃, resuiting in a remarkable increase in both strength and ductility of the alloys. After the solution and aging treatment, the mechanical properties of the alloys are much higher than those under as-cast conditions and optimum properties are obtained from the specimens aged directly after extrusion. As a resuit, Sm can be considered as an additive element to make wrought magnesium alloys stronger.
出处
《东南大学学报(自然科学版)》
EI
CAS
CSCD
北大核心
2009年第3期610-614,共5页
Journal of Southeast University:Natural Science Edition
基金
国家科技支撑计划资助项目(2006BAE04B07)
关键词
镁
钐
合金
挤压
时效
脱溶
Mg
Sm
alloy
extrusion
aging
precipitation