原位Al_2O_3颗粒增强铝基复合材料的高能超声制备及性能研究

Study on the ultrasonic fabrication and property of in situ Al_2O_3 particle reinforced aluminum matrix composites

采用反应烧结和熔体超声分散法,以SiO2为原料成功制备了Al2O3颗粒增强铝基复合材料。利用X射线衍射仪、差热分析仪、扫描电镜、能谱仪等分析了复合材料的显微组织、生成的颗粒以及颗粒的形貌、尺寸和颗粒的分布。利用电子式万能试验机进行室温拉伸实验。结果表明,在800℃下,经过8h烧结后的坯块中SiO2完全反应生成了团聚的Al2O3颗粒,Al2O3颗粒粒度约为1μm。在熔体中施加1.0kW/cm2的高能超声使坯块熔化,获得的复合材料中Al2O3颗粒分布均匀,颗粒尺寸基本没有变化;复合材料的抗拉强度110.6 MPa,较纯铝基体的92.0MPa,提高了20.2%。

Reaction sintering and ultrasonic treatment were used to synthesize AI2O3 particles reinforced alumi hum matrix composites from SiO2powder. Mitrostrutture of the composite , the morphology and the size of the particles as well as the particles distribution in the as prepared composites were investigated by X-ray diffrat tion, differential thermal analysis, scanning electron microscope, and energy dispersive spectroscopy. Electron it universal testing machine was used dor room temperature tensile experiment. It was shown that Al2O3 parti ties, which were about 1 μm in size, have been obtained and aggregate in the compact sintered at 800 ℃ for 8 h. Composites with uniformly distributed Al2O3 particles were obtained by dissolving the as sintered compact in liquid alunlinum under high energy ultrasound with a power of 1.0 kW/cm-2. The size of Al2O3 particles alter dissolving almost had no change. The tensile strength of the composite was 110.6 MPa, which was increased by 20.2 % compared with pure aluminium （92.0 MPa）.