Mg-Zn系合金沉淀硬化研究进展

Research Progress on Precipitation Hardening of Mg-Zn System Alloys

Mg-Zn系合金因具有显著的沉淀硬化效果,成为最具发展前景的结构材料之一。通过微合金化调控沉淀相行为、增加沉淀密度并减少颗粒间距,可进一步增强其沉淀硬化效果。微合金化元素可分为稀土、碱土以及其他元素,其中稀土元素可使沉淀相密度增加,碱土元素不仅能增加沉淀相密度,还能细化第二相,其他微合金化元素可在时效过程中提高沉淀相形核率,并加速沉淀过程。本文综述了Mg-Zn系合金沉淀行为的析出热力学以及析出序列的研究进展,归纳了微合金化元素对沉淀强化的作用,展望了Mg-Zn沉淀镁合金领域今后的研究方向。

Mg-Zn system alloys have become one of the most promising structural materials owing to the significantly precipitation strengthening.The impact of precipitation strengthening can be further improved by increasing the precipitation density and decreasing the particle spacing,which can be achieved by microalloying to control the precipitation behavior.Microalloyed elements include rare earth elements,alkaline earth elements and other elements.Rare earth elements can increase the density of precipitation,alkaline earth elements can refine the precipitation particles as well as increase precipitation density,other elements can increase the nucleation rate of precipitation and accelerate precipitate process.In pre-sent paper,the research progress of precipitation thermodynamics and precipitation sequence of Mg-Zn system alloys are reviewed,the effects of microalloyed elements on precipitation strengthening are summarized,and research direction of precipitation strengthening of Mg-Zn alloys is prospected.