【摘要】 采用混合盐反应工艺制备了A356/TiB2铝基复合材料,通过OM,XRD,SEM,TEM和力学拉伸试验等材料分析方法测试了所合成复合材料的微观组织和力学性能。研究表明:K2TiF6和KBF4混合盐在A356铝合金熔体温度850℃时反应生成的增强体为棒状和粒状TiB2,并在基体中呈均匀弥散分布,增强体与基体间未发生界面反应。由于原位TiB2颗粒的强化和细化晶粒作用,使复合材料的力学性能明显提高,经热处理后共晶Si发生球化。复合材料拉伸断口呈韧性断裂特征,增强颗粒与基体间界面的破坏以脱开机制为主。更多还原

【Abstract】 In situ A356/TiB2 composites were prepared by LSM technique. The microstructures and mechanical properties of the prepared composites were observed and measured using optical morphology, X-ray diffraction, scanning electronic microscopy and transmission electronic microscopy. The results showed that in situ TiB2 particles with bar and sphere shapes formed in the reaction of flux in A356 alloy melt at a temperature of 850℃ and were distributed homogeneously in the matrix without interface reaction. It was substantiated that the matrix was reinforced and refined effectively by TiB2 particles resulting in the mechanical properties of the composites increasing obviously compared with the matrix alloy and the fracture of the composites displayed ductile failure mode.更多还原