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

为了镁合金的回收利用，在AZ31合金的加工切屑中加入不同含量的铝和锌粉，进行不同铣削次数的Mg-Zn和Mg-AI-Zn粉混合物的机械合金化。用x射线衍射研究了粉末中形成的晶相，并测量了机械合金化粉末颗粒的维氏硬度以确认形成的相。在Mg-12mol%Al中形成镁相的过饱和固溶体，其晶粒尺寸为纳米级。在低Al含量的粉末混合物中，固溶体与Mg_<17>Al_<12>形成共晶结构。在高铝含量的情况下，金属间化合物的形成，这些晶体在长时间的磨矿后变成非晶相。在Mg-Al-Zn三元体系中，通过机械合金化（MA）形成的二十面体Mg_<49>(AI, Zn)_<32>相称为准晶体。为了改善镁合金的表面，将得到的MA粉末堆积在镁合金板上，然后在不同温度下进行热轧。在滚接过程中，Mg和Al通过扩散现象在MA层和镁合金板的界面上相互混合。将制备的MA粉末作为基体叠置在镁合金棒上，在不同温度下进行热压缩变形粘接。然后，研究了结合MA合金层的磨损和腐蚀性能。通过高硬度MA合金层的粘接，可以提高镁合金的耐磨性。当MA合金层被盐水喷射超过28.8k时，其表面的腐蚀实际上并没有进展。

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.