Research On Squeeze Casting Of High Toughness Mgnesium Alloys

Resource and environment are chiefly matter of continuable development in 21st. At present, many traditional metal mine gradually dry up. But magnesium alloys, as a structural material family, have many advantages, such as high specific strength, high specific rigidity, good casting capability and easy to recycle etc. So magnesium alloys are mass used in automobile,airplane,computer and communication equipment etc. But potential of magnesium has not been sufficiently rootled. The accelerating development of magnesium alloys is one of important task of societal continuable development.Microstructure and mechanical performance are influenced by squeeze casting was researched in this experiment, and Al or Zn is appended into AM60 magnesium alloy which how about influence the microstructure and mechanical performance of magnesium alloy also was studied. Based on AM60 magnesium alloy, we studied the relationship between microstructure,process parameter and mechanical performance. All of these study data for optimize process parameter of squeeze casting provided parameter. The research showed that crystals of squeeze casting are finer than that of gravity casting. The α phase dendrite was refined, and β phase was refined and distribution continuous. A lot of dendrite emerged in microstructure.Pressure is one of important parameter of squeeze casting process. Under the pressure of 80MPa, the ultimate tensile strength, yield strength,elongation and rigidity respectively is 208.5MPa, 152.85, 11% and 62.3HRE. Compared with gravity castings, the ultimate tensile strength,yield strength and elongation of squeeze casting is separately improved 30%,52.9% and 90% . Aluminium is the most important metal element which influence magnesium alloys. Alunisium can improve magnesium alloys,s intension and rigidity, and make magnesium alloys easy to casting. Followed with aluminium content increasing, the crystal of magnesium became discontinuous. The comprehensive mechanical properties of magnesium alloys which contained 6% content aluminium is best in this experiment.When Zn was added into AM60, the crystal boundary became narrow and shallow, the β phase is decreasing trend and became discontinuous. The mechanical properties of magnesium alloys is sharply descend when Zn was added into magnesium.