原位Al_2O_3颗粒增强Al-10Si基复合材料制备的研究

Study on the preparation of in situ Al_2O_3 particle reinforced Al-10Si matrix composites

基于SiO2/Al-10Si反应体系,通过半固态机械搅拌法及高能超声处理组合工艺,成功制备出Al2O3颗粒增强铝基复合材料。SiO2粉体预处理及铝熔体Mg元素活化有效改善了两者间的润湿性,在转速700r/min、搅拌10min的条件下,可获得SiO2颗粒均匀分布的微观组织;升温后,经过高能超声进一步熔体处理,不仅促进了SiO2/Al的原位置换反应,而且空化消除了残余气体。金相显微镜(OM)、X射线衍射仪(XRD)、扫描电子显微镜(SEM)和能谱仪(EDS)的分析检测表明,原位生成的Al2O3颗粒均匀地分布于Al-Si合金基体中。

Based on the SiO 2/Al-10Si reaction system,Al2 O 3 particle reinforced aluminum matrix composites was successfully prepared through the combined process of semi-solid mechanical stirring and high-energy ultra-sound treatment.Pretreatment of SiO 2 powder and activation of aluminum melt by Mg improve the wettability of each other.Under the condition of a 700 r/min stirring speed and a 10 min stirring time,uniform distribution of SiO 2 particles can be obtained.After the temperature increased,a further step of the high-energy ultrasonic treatment to the melt followed,not only promoting the in-situ displacement reaction of SiO 2 and Al,but also eliminating the residual gas by acoustic cavitation.The analysis through optical microscopy （OM）,X-ray dif-fraction （XRD）,scanning electron microscopy （SEM）and energy dispersive spectroscopy （EDS）showed that in situ processed Al2 O 3 particles distributed uniformly in the aluminum silicon alloy matrix.