1.Introduction Casting accounts for over 90%of magnesium-based alloy applications with die-cast and thixomolded parts dominating.The high strength-to-weight ratio coupled with excellent fluidity,low volumetric latent ...1.Introduction Casting accounts for over 90%of magnesium-based alloy applications with die-cast and thixomolded parts dominating.The high strength-to-weight ratio coupled with excellent fluidity,low volumetric latent heat and heat capacity,reduced cycle times,and low soldering tendencies,all make magnesium alloys excellent choices for die casting applications.Despite these advantages,in recent years,the use of magnesium in die casting applications has been declining.展开更多
This paper presents a re-evaluation of the room temperature mechanical properties and high temperature creep resistance of magnesium die-casting alloy AE44(Mg-4Al-4RE)in light of the influence of minor Mn addition.It ...This paper presents a re-evaluation of the room temperature mechanical properties and high temperature creep resistance of magnesium die-casting alloy AE44(Mg-4Al-4RE)in light of the influence of minor Mn addition.It is shown that the Mn-containing AE44 exhibits distinct age hardening response upon direct ageing(T5)due to the precipitation of nanoscale Al-Mn particles,as reported previously in a similar alloy.The T5 ageing leads to a significant improvement in strength with similar ductility.Consequently,the T5-aged AE44 has a remarkably better strength-ductility combination than most Mg die-casting alloys and even the Al die-casting alloy A380.Minor Mn addition is also shown to be critical for the creep resistance of AE44 whereas the influence of the RE constituent is not as significant as previously thought,which reaffirms that precipitation hardening of theα-Mg matrix is more important than grain boundary reinforcement by intermetallic phases for the creep resistance of die-cast Mg alloys.The findings in this work could provide new application perspectives for AE44,particularly in the automotive industry.展开更多
文摘1.Introduction Casting accounts for over 90%of magnesium-based alloy applications with die-cast and thixomolded parts dominating.The high strength-to-weight ratio coupled with excellent fluidity,low volumetric latent heat and heat capacity,reduced cycle times,and low soldering tendencies,all make magnesium alloys excellent choices for die casting applications.Despite these advantages,in recent years,the use of magnesium in die casting applications has been declining.
基金supported by Australian Research Council(LP160100690)Magontec Ltd.Monash Centre for Electron Microscopy(MCEM)。
文摘This paper presents a re-evaluation of the room temperature mechanical properties and high temperature creep resistance of magnesium die-casting alloy AE44(Mg-4Al-4RE)in light of the influence of minor Mn addition.It is shown that the Mn-containing AE44 exhibits distinct age hardening response upon direct ageing(T5)due to the precipitation of nanoscale Al-Mn particles,as reported previously in a similar alloy.The T5 ageing leads to a significant improvement in strength with similar ductility.Consequently,the T5-aged AE44 has a remarkably better strength-ductility combination than most Mg die-casting alloys and even the Al die-casting alloy A380.Minor Mn addition is also shown to be critical for the creep resistance of AE44 whereas the influence of the RE constituent is not as significant as previously thought,which reaffirms that precipitation hardening of theα-Mg matrix is more important than grain boundary reinforcement by intermetallic phases for the creep resistance of die-cast Mg alloys.The findings in this work could provide new application perspectives for AE44,particularly in the automotive industry.
