摘要
Cast ZM21 magnesium alloys were subjected to symmetric extrusion at four different temperatures（200,250,300 and 350 ℃） with three extrusion ratios of 4：1,9：1 and 16：1,respectively.The effects of extrusion parameters such as temperature and extrusion ratio were studied by optical microscopy,X-ray diffraction（XRD） and tensile test.The optical micrographs exhibited various stages of recrystallization,i.e.,partial to full recrystallization influencing mechanical properties to good extent.Higher extrusion temperature resulted in coarse grains,whereas finer grains were obtained at higher extrusion ratios.Ultimate tensile strength of this alloy was increased from 160 MPa to 316 MPa after extrusion at 250 ℃ with an extrusion ratio of 9：1.
对铸态ZM21镁合金在不同温度(200,250,300和350℃)与不同挤压比(4:1,9:1,16:1)下进行挤压。借助光学显微镜、X射线衍射仪(XRD)和拉伸试验来研究挤压参数(温度和挤压比)的影响。挤压钛合金的光学显微组织呈现出不同阶段的再结晶组织,从部分到完全再结晶,进而影响到合金的力学性能。较高的挤压温度会导致生成粗大的晶粒,然而,较高的挤压比导致细小的晶粒。在250℃、挤压比9:1下挤压后,合金的极限拉伸强度从160MPa增加到316MPa。
