Abstract
The effects of heat treatment on the microstructure and mechanical properties of ZA84 (Mg-8Zn-4Al-0.25Mn) alloy were investigated. The results indicate that the as-cast microstructure of the alloy is mainly composed of α-Mg matrix and two different morphologies of precipitates (continuous and quasi-continuous Mg 32(Al, Zn) 49 phases and isolated Mg 5Al 2Zn 2 phases). After solid solution treatment at 345°C, the Mg 32(Al, Zn) 49 phases change from continuous and quasi-continuous net to disconnected acute angle shape, and parts of second phases sphericize. The optimum heat treatment condition for the alloy is solution treatment at 345°C for 48 h and water quenching, then aging treatment at 200°C for 12 h and atmosphere cooling. Under the optimum condition, the ultimate tensile strength and yield strength of the alloy can be improved, but the elongation is not effected much by heat treatment.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
