搅拌温度对双粒径混合SiC_p/ZL107复合材料的影响

Effect of stirring temperature on SiC_p/ZL107 composites with two kinds of dianeter particles

采用搅拌熔铸法制备双粒径SiCp/Al复合材料,利用扫描电镜(SEM)、电子万能试验机研究搅拌温度对复合材料的微观结构以及力学特性的影响。结果表明:SiC含量随着搅拌温度的升高而增加,在585℃两种粒径混合的SiC颗粒弥散分布在基体上,随温度继续升高,基体出现明显的贫SiC区域;复合材料的抗压强度、抗弯强度以及最大弯曲挠度均随着搅拌温度的升高先增大后减小,在585℃达到最大值,力学特性较纯铝、单一粒径的SiCp/ZL107复合材料有明显提高。SiC颗粒的分布以及界面结合强度决定复合材料的断裂机制。

SiCp/ZL107 composites with two particle sizes were prepared by stirring casting. The influence of stirring temperature on microstructure and mechanical properties of the composites was investigated by scanning electron microscopy （SEM）, energy dispersive spectroscopy （EDS） and electronic universal testing machine. The results show that the content of SiC increases with the increase of stirring temperature, and the SiC particles with two particle sizes are diffusely distributed on the substrate when the stirring temperature is 585 ℃. There is an obvious poor SiC region with the continuous increase of stirring temperature. The compressive strength, flexural strength, and maximum deflection of composites along with the stirring temperature increases first and then decreases, reaches its maximum at 585 ℃. Compared with the pure aluminum and single particle size SiCp/ZL107 composites, the mechanical properties of two particle sizes SiCp/ZL107 composites increase significantly. The failure mechanism of the composites is determined by the distribution of SiC and the interfacial bonding strength.