CAJ | 학술논문

利用真空感应炉在氩气保护下，设计与制备Mg-8Li-3Al-0.5Mn-xSr (x=0~1.0)合金，并将其进行热挤压处理。分别研究合金铸态与挤压态显微组织和拉伸性能。结果表明：LAM830合金主要含有α-Mg，β-Li，Al2Mn3和LiMgAl2相。在加入Sr后合金中出现Al-Sr析出相。Sr对铸态合金α-Mg基体的二次枝晶臂有明显细化效果。经过热挤压处理的合金组织远优于铸态的合金组织。金属间化合物的含量与形态对合金力学性能的影响很大，其中挤压态的LAM830-0.5Sr具有最佳的伸长率(22.43%)，LAM830-0.75Sr合金具有最佳的抗拉强度(265.46 MPa)。
이용진공감응로재아기보호하，설계여제비Mg-8Li-3Al-0.5Mn-xSr (x=0~1.0)합금，병장기진행열제압처리。분별연구합금주태여제압태현미조직화랍신성능。결과표명：LAM830합금주요함유α-Mg，β-Li，Al2Mn3화LiMgAl2상。재가입Sr후합금중출현Al-Sr석출상。Sr대주태합금α-Mg기체적이차지정비유명현세화효과。경과열제압처리적합금조직원우우주태적합금조직。금속간화합물적함량여형태대합금역학성능적영향흔대，기중제압태적LAM830-0.5Sr구유최가적신장솔(22.43%)，LAM830-0.75Sr합금구유최가적항랍강도(265.46 MPa)。
The as-cast Mg-8Li-3Al-0.5Mn-xSr (LAM830-xSr, x=0-1.0) alloys were designed and prepared in a vacuum induction furnace under controlled argon atmosphere. The alloys were then processed by hot extrusion, and their microstructural evolution and mechanical properties were analyzed. Results indicate that the LAM830 alloy mainly consists ofα-Mg,β-Li, Al2Mn3, and LiMgAl2 phases. Sr addition results in the precipitation of Al-Sr. Moreover, Sr addition results in a fact that the secondary dendrite arm spacing (DAS) of the primaryα-Mg phase is obvious refined. Microstructure of the investigated alloys is further refined as a result of the hot extrusion treatment. The content and morphology of the secondary phases have important effects on the mechanical properties of the alloys. The as-extruded LAM830-0.5Sr alloy exhibits an optimal elongation of 22.43% and as-extruded LAM830-0.75Sr alloy shows an optimal tensile strength of 265.46 MPa.