工艺参数对AZ91HP镁合金压铸件晶粒尺寸的影响  

Effects of Processing Parameters on Grain Size in Die Casting Magnesium Alloy AZ91HP Castings

作　　者：付振南[1] 曹运锋[1] 熊守美[1] 

机构地区：[1]清华大学

出　　处：《特种铸造及有色合金》2006年第7期436-438,共3页Special Casting & Nonferrous Alloys

基　　金：国家重点基础研究发展计划(973计划)项目(2005CB724100);清华-东洋镁铝合金成形技术研究开发中心资助项目

摘　　要：研究了浇注温度、模具温度和内浇道速度对镁合金压铸件抗拉强度和晶粒尺寸的影响规律。结果表明,随浇注温度和内浇道速度的升高,试样的抗拉强度先增大再减小,晶粒尺寸则先减小再增大;当模具温度升高时,试样的抗拉强度随着模具温度升高而增大,晶粒尺寸则随之减小。当压铸工艺参数(浇注温度680℃、模具温度为215℃、内浇道速度为70m/s)适宜时,AZ91HP合金标准拉伸试棒的抗拉强度σb稳定在224.2MPa,密度ρ稳定在1.77g/cm3,晶粒尺寸只有14.4μm。通过线性回归建立了晶粒尺寸和抗拉强度之间的经验关系。Effects of processing parameters, including the pouring temperature, the die temperature, the ingate velocity, on tensile strength and grain size of die casting Mg alloy AZ91 HP have been investigated. The results show that with the increase of the pouring temperature and ingate filling velocity, the tensile strength is increased firstly and then decreased, while grain size is decreased firstly and then increased. However, with increasing in die temperature, tensile strength of the castings is improved and grain size is decreased. The tensile strength of 224.2 MPa and density of 1.77 g/cm^3 of the samples with grain size of 14.4 μm can be observed at the pouring temperature of 680 ℃ and die temperature of 215 ℃ and ingate velocity of 70 m/s. Finally, an empiric formula between the grain size and tensile strength is established through linear regression.

关 键 词：压铸 镁合金 工艺参数 晶粒尺寸 

分 类 号：TG249.2[金属学及工艺—铸造]