热轧变形对Al_(18)B_4O_(33)W/Al复合材料结构与拉伸性能的影响

Effect of Rolling on Microstructures and Tensile Properties of Al_(18)B_4O_(33)W/Al Composite

采用挤压铸造工艺制备了硼酸铝晶须增强纯铝基复合材料,并在450℃高温下对复合材料实现了轧制比为50%的热轧变形.利用扫描电子显微镜(SEM)和透射电子显微镜(TEM)对轧制前后复合材料的微观组织结构进行了观察,并对轧制前后复合材料的室温拉伸性能进行了测试.研究结果表明,热轧制变形虽然导致硼酸铝晶须增强铝基复合材料中晶须发生了不同程度的折断,但却能在很大程度上提高硼酸铝晶须沿轧制方向的定向排列程度,并且有利于复合材料中界面结合强度的提高以及复合材料内部微观裂纹的愈合,从而大幅度改善复合材料沿轧制方向上的拉伸性能.

In the present work,pure Al matrix composites reinforced with Al（18）B）4O（33） whiskers fabricated using squeeze casting were rolled to 50% reduction at 450 ℃. The microstructure characterizations of the composites before and after rolling were carried out on the scanning electron microscope（ SEM） and transmission electron microscopy（ TEM）. And the tensile properties of the as-cast and rolled composites were tested at room temperature. The result shows that rolling deformation results in the whisker fracture,but can improve the whisker orientation arrangement degree,enhance the Interface bonding strength and heal the micro-cracks in the composites,which can result in the tensile property improvement of composites along the rolling direction.