机构地区: 重庆科技学院冶金与材料工程学院
出 处: 《材料热处理学报》 2012年第6期70-73,共4页
摘 要: 研究了挤压工艺参数(挤压温度、挤压比)对Mg-Sr-Y中间合金组织和性能的影响。结果表明:Mg-Sr-Y中间合金的铸态组织是由树枝晶状的基体相α-Mg、沿晶分布的网状共晶组织(Mg17Sr2+Mg25Y4)组成;热挤压后合金的晶粒明显细化,树枝晶和网状组织被打碎,晶粒大小和合金中析出相的分布更均匀。同时挤压后合金的硬度显著提高,力学性能明显改善,形变强化效果较为显著,其强化效果与挤压温度和挤压比有关。挤压温度越高,挤压比越大,则强化效果越显著。 Effects of extrusion process parameters (extrusion temperature, extrusion ratio) on microstrueture and performance of Mg-Sr-Y alloy were studied. The results indicate that the as-cast microstructure of Mg-Sr-Y alloy is composed of dendritic matrix phase α-Mg and network eutectic (Mg17Sr2 , Mg25Y4) distributed along grain boundaries. After hot extrusion, the alloy grains are refined significantly, the network autectic and dendrite structure is broken up, and grain size and distribution of the second phase of alloy are more uniform. Meanwhile, hardness of the alloy significantly increases, and the mechanical properties are improved obviously due to strain hardening effect. The effect of strengthening depends on extrusion temperature and extrusion ratio. The higher the extrusion temperature and the larger extrusion ratio, the strengthening effect is more significant.