纳米相复合Al-Sn合金的反应球磨制备及性能研究

Synthesis of Nano-phase Composite Al-Sn Alloy by Reaction Ball Milling Process and Its Performance

利用反应球磨制备Al-SnO_2-MgH_2粉末,然后通过压制和烧结制备出高热稳纳米相复合结构Al-Sn合金。运用X射线衍射仪(XRD)和扫描电镜(SEM)等研究反应球磨制备的纳米相复合Al-Sn合金的组织和性能。结果表明:采用两步法和添加MgH_2组元的方式所制备的机械合金化(MA)Al-SnO_2-MgH_2复合粉末,经压制和600℃烧结,合金中的SnO_2几乎全部被还原成单质Sn,并呈现双尺度结构。其中,共生反应形成的纳米级Sn粒子和Al_2O_3颗粒均匀弥散地分布在Al基体中,显著提高了合金的硬度,从而使合金表现出低的摩擦系数和磨损量。

Reaction ball milling process was used to prepare Al-SnO2-MgH2 alloy powders, then a high thermal stability nano- composite Al-Sn alloy was obtained by a combination of cold pressing and sintering. The effect of reaction ball milling process on the microstructure and properties were investigated by XRD and SEM. The results show that the SnO2 in the MA Al-SnO2-MgH2 alloy powder, which was produced by a two steps method with the addition of MgH2, was almost deoxidized into monolithic Sn after sinte- ring at 600 ℃. Meanwhile, the in situ formed Sn exhibits a typical dual-scale structure. In particular, the symbiotic formed Sn and Al2O3 were in nano-size and homogeneously distributed in the AI matrix, improving the hardness obviously and resulting in a signifi- cantly reduction of friction coefficient and wear volume.