摘要
将铸态Mg-5Sn-1.5Al-1Zn-0.8Si镁合金进行往复挤镦变形,采用OM、SEM和EDS等分析合金组织,重点研究了往复挤镦对该合金显微组织、力学性能及断口形貌的影响。结果表明:多道次往复挤镦可显著细化实验合金的显微组织,经过挤镦变形后,平均晶粒尺寸由铸态的50μm细化至3μm左右,组织中的第二相被破碎且呈现弥散分布。往复挤镦可大幅度提高实验合金的力学性能,其硬度、抗拉强度和延伸率分别比铸态试样提高了47%、155%和110%,挤镦变形合金的拉伸断口出现大量韧窝,断裂方式为典型的韧性断裂。
As-cast Mg-SSn 1.5AI-IZn-0. 8Si magnesium alloy was processed by reciprocating extrusion （RE）. Microstructure of the alloy was studied with OM, SEM and EDS. Effects of reciprocating extrusion on microstruc ture, mechanical property and fracture morphology were particularly discussed. The results indicate that multi pass reciprocating extrusion has the strong refinement on microstructure, the average grain size of as cast decreases from 50 μm to 3 /ma after reciprocating extrusion, second-phase is broken and dispersive distribution. Reciprocating extrusion can greatly improve mechanical property of the alloy. Compared with as-cast alloy, the hardness, tensile strength and elongation of reciprocating extrusion alloy are increased by 47%, 155%and 110% respectively. After reciprocating extrusion, the tensile fracture of the alloy appears massive dimples, and fracture mode is typical ductile fracture as well.
出处
《材料导报》
EI
CAS
CSCD
北大核心
2013年第4期36-39,共4页
Materials Reports
基金
河南省重点攻关项目(102102210031)
河南理工大学金属材料发展基金(506096)
关键词
往复挤镦
镁合金
显微组织
力学性能
断口形貌
reciprocating extrusion upsetting, magnesium alloy, microstructure, mechanical property, fractureappearance
