The effects of Zn additions on the age hardening response and microstructure of Mg-9Al-6Sn (wt.%) alloy have been investigated. It is found that the Zn additions can remarkably increase the alloy hardness in the as-quenched condition. The peak hardness value of the Mg-9Al-6Sn alloy increases from 90 ± 0.87 HV to 103 ± 3.83 HV, when the Zn addition is 3 wt.%, which is the highest among the magnesium casting alloys that are free of rare-earth elements. The enhanced hardness in the Mg-9Al-6Sn-3Zn alloy is attributable to an increased volume fraction of smaller Mg2Sn particles in the solution-treated condition and the formation of Mg Mg17Al12 rods and Mg21(Zn, Al)17 precipitates in the peak-aged condition.
- Magnesium alloy
- Mechanical properties