Eco-material process of magnesium alloys by mechanical alloying and environmental strength of its alloy.

为了实现镁合金的回收利用，在AZ 31镁合金切屑中加入不同含量的铝粉和锌粉，对Mg-Zn和Mg-Al-Zn混合粉末进行机械合金化处理，并进行不同球磨时间的合金化处理。通过X射线衍射研究在所得粉末中形成的晶相，并测量机械合金化粉末颗粒的维氏硬度以确认所形成的相。Mg-12mol%Al合金中形成了镁相的过饱和固溶体，其晶粒尺寸为纳米级。在低Al含量的混合粉末中，固溶体与Mg_ Al_3形成共晶结构<17><12>。在高Al含量的情况下，金属间化合物的形成屈服，并且这些晶体在延长的球磨时间后变成非晶相。在Mg-Al-Zn三元系中，通过机械合金化（MA）形成了二十面体Mg_<49>（Al，Zn）_<32>2相，称为准晶相。为了改善镁合金的表面，将所得MA粉末堆叠在镁合金板上，然后在不同温度下进行热轧。轧制复合时，镁铝在MA层与镁合金板的界面处通过扩散相互混合。此外，将所得MA粉末堆叠在镁合金棒上作为基底，并在不同温度下通过热压变形将它们连接起来。研究了粘结层的磨损和腐蚀性能。高硬度的MA合金层的结合可以提高镁合金的耐磨性。在盐水喷涂28.8ks以上时，MA合金层的表面几乎没有发生腐蚀。

For recycle of magnesium alloy, Mg-Zn and Mg-AI-Zn powder mixtures, which aluminum and zinc powder were added with various contents to machined chips of AZ31 alloy, were mechanically alloyed for various milling times. Crystal phase formed in the obtained powder was investigated by X-ray diffraction and Vickers hardness of the mechanically alloyed powder particles was measured for confirmations of the formed phases. Super-saturated solid solutions of the magnesium phase are formed in the Mg-12mol%Al, its crystalline size has a nanometer scale. The solid solutions are formed the eutectic structure together with Mg_<17>Al_<12> in the powder mixtures with low Al contents. In the case of the high Al contents, the formation of the intermetallic compounds yields, and these crystals become to amorphous phase after the prolonged milling time. In the case of Mg-Al-Zn ternary system, icosahedron Mg_<49>(AI, Zn)_<32> phase as called the quasi crystal forms by the mechanical alloying(MA). For the surface improvements of the magnesium alloy, the obtained MA powders were stacked on magnesium alloy sheets, then hot-rolled at various temperatures. When roll-bonding were performed, Mg and Al mixed each other by diffusion phenomenon in interface of MA layer and Mg alloy sheet. Moreover, the obtained MA powders were stacked on magnesium alloy rod as the substratum, and they were bonded by hot-compressive deformation at various temperatures. And then, wear and corrosion properties of the bonded MA alloy layer were investigated. The wear resistance of magnesium alloy can be improved by the bonded of the MA alloy layer of high hardness. Corrosion has not practically progressed on surfaces of the MA alloy layers when they were saltwater-sprayed for over 28.8ks.