热处理对AZ91D镁合金组织及力学性能的影响

Effect of heat treatment on structure and mechanical properties of AZ91D magnesium alloys

结合Mg-Al二元相图,研究不同时间固溶处理对AZ91D镁合金力学性能的影响,以及固溶时效处理后镁合金组织、性能的变化.结果表明,随着固溶处理时间的延长,AZ91D镁合金中的β相逐渐分解并溶入α相中,固溶处理5 h后,β相完全分解;继续延长固溶处理时间,AZ91D镁合金中的合金元素在扩散机制的作用下趋向均匀.研究还发现,AZ91D镁合金经415℃×10 h和415℃×24 h固溶处理后力学性能最优,且经时效处理后这2组工艺仍具有最优的力学性能.

Incorporating with Mg-Al phase diagram, the effects 05 solid solution treatment for different time-periods on mechanical properties of magnesium alloy AZ91D, and the variation of its microstructure and properties after aging treatment were investigated. With the extension of solid solution treatment time, β-phase in AZglD decomposed gradually and dissolved in α-phase. After 5 h solid solution treatment, the phase decomposed completely. Continue to extend the treatment time, the alloying elements in the alloy approached to a uniform state because of the proliferation mechanism. The study found that AZ91Dmagnesium alloy treated with 415 ℃×10 h and 415 ℃× 24 h solid solution treatment exhibited the best mechanical properties, and after aging treatment, these two groups had the best performance, too.