摘要
研究了利用应变诱发熔体激活法SIMA(Strain InducedMeltActivation)制备AZ91D镁合金半固态非枝晶时的组织转变过程.实验结果表明:具有树枝晶形态的AZ91D合金经20%及30%的预变形后,在半固态升温(540~580℃)或保温(570℃)过程中,其组织形貌由粗化的等轴晶及短树枝晶依次转变为小块状细晶粒→团块状→球状大晶粒.另外,在等温热处理过程中,试样内部体系寻求能量最低状态也是组织转变的一个不可忽略的因素.与未预变形的合金制备的非枝晶组织相比较,经预变形处理的试样是较好的半固态成型材料.
The structural evolution of semisolid AZ91D alloy with nondendrites produced by using the method of StrainInduced Melt Activation (SIMA) is studied. The results indicate that, after AZ91D alloy with dendrites experienced 20% and 30% prior compressive deformation, its microstructure changes in turn from coarse equiaxed grains with short dendrites, into small lumpish fine grains, agglomerate grains, and big spherical grains during the process of isothermal heattreatment at semisolid temperature between 540℃ and 580℃. In addition, it should not be neglected that the system in the sample seeks for the lowest energy condition during the semisolid isothermal heattreatment. The SIMA AZ91D alloy fits well to the requirement of semisolid forming compared with the original AZ91D alloy.
出处
《甘肃工业大学学报》
北大核心
2002年第4期34-38,共5页
Journal of Gansu University of Technology
基金
甘肃省中青年科技基金储备项目(YS 011 A22 009)