摘要
采用正交试验方法、半固态流变压铸成形工艺和高剪切速率双螺杆机械搅拌机,对半固态法制备镁合金工艺进行了优化。结果表明:搅拌机筒体温度对半固态浆料固相率和初生α-Mg相圆整度的影响最大,双螺杆剪切速率对初生α-Mg相晶粒平均尺寸的影响最大;试验条件下的最佳工艺参数为镁液浇注温度605℃,筒体温度575℃,螺杆剪切速率6 830 s-1;所得镁合金的力学性能σb=216 MPa,δ=2．3％,硬度74 HB。
The semi-solid preparation process optimization of magnesium alloy had been studied by positive alternation method with rheo-diecasting process and twin-screw in high shear rate. The results shows that the solid fraction of semi-solid slurry and the round degree of primary α-phase are intensively influenced by barrel temperature of screw mixer, and the primary grain size is mainly controlled by shear rate of twin-screw. The pertinent processing parameters are summarized as follows： pouring temperature of the Mg melt is 605℃; barrel preheating temperature is 575℃ and shear rate is 6 830 s^-1. The tensile strength, elongation and hardness of semi-solid AZ91D alloy are 216 MPa, 2. 3% and 74 HB.
出处
《机械工程材料》
CAS
CSCD
北大核心
2006年第11期10-12,35,共4页
Materials For Mechanical Engineering
基金
湖北省重点科技计划资助项目(20002P0304)
科技部中小企业技术创新基金资助项目(01C26214200911)
关键词
半固态
镁合金
双螺杆
微观组织
力学性能
semi-solidl magnesium alloy
twin-screw
microstructure
mechanical property
