摘要
AZ91D alloy components were cast by low pressure die casting (LPDC) process. The mechanical properties of cast components with different microstructural features (shrinkage and distribution of Mg17Al12 second phase) were investigated under as-cast states. Compared with gravity casting, AZ91D with LPDC has much coarser grain size and second phases(Mg17Al12 and Al8Mn5). The different size and distribution of Mg17Al12 phase and shrinkage correspond to different mechanical properties. The ultimate tensile strengths and elongations are mainly decided by the content and distribution of shrinkage porosity, while the yield strengths are determined by the percentage and distribution of Mg17Al12 phase. The more and finer Mg17Al12 phase in the alloy, the relatively higher the yield strengths are. In the alloy without shrinkage, the mechanical properties are mainly determined by the size and distribution of Mg17Al12 phase. The finer Mg17Al12 phase, the better the mechanical properties are. Under optimal process, the density and mechanical properties of LPDC AZ91D are improved with fine microstructures.
AZ91D alloy components were cast by low pressure die casting （LPDC） process. The mechanical properties of cast components with different microstructural features （shrinkage and distribution of MgtTAlt2 second phase） were investigated under as-east states. Compared with gravity casting, AZ91D with LPDC has much coarser grain size and second phases（Mg17Al12 and Al8Mn5）. The different size and distribution of Mg17All2 phase and shrinkage correspond to different mechanical properties. The ultimate tensile strengths and elongations are mainly decided by the content and distribution of shrinkage porosity, while the yield strengths are determined by the percentage and distribution of Mg17Al12 phase. The more and finer Mg17Al12 phase in the alloy, the relatively higher the yield strengths are. In the alloy without shrinkage, the mechanical properties are mainly determined by the size and distribution of Mg17Al1l2 phase. The finer Mg17Al12 phase, the better the mechanical properties are. Under optimal process, the density and mechanical properties of LPDC AZ91D are improved with fine microstructures.
出处
《中国有色金属学会会刊：英文版》
CSCD
2006年第A03期1690-1693,共4页
Transactions of Nonferrous Metals Society of China
关键词
镁合金
微观结构
机械性能
低压条件
金相
AZ91 D
magnesium alloys
low pressure die cast
microstructure
porosity
mechanical property
