建立了Al2O3sf/2A12铝基复合材料液态浸渗挤压表面缺陷预测的数学模型, 基于L9(34)正交试验实验表模拟了9种在不同工艺参数下液态浸渗挤压成形Al2O3sf/2A12铝基复合材料制件的损伤分布规律, 研究了工艺参数对损伤形成的影响规律. 结果表明: 由于不均匀变形以及制件表面的局部过热, 在坯料模角处易产生表面环向裂纹; 保压时间对表面损伤形成的影响最大, 其次为浇注温度和模具预热温度, 挤压速度的影响比较小. 通过优化工艺参数, 可以有效地避免表面损伤的产生, 挤出表面质量良好的制件, 模拟结果与实验结果基本吻合.
A model for predicting the surface damage of Al2O3sf/2A12 composites by liquid infiltration-extrusion process was established, and the distribution of surface damage was obtained under nine groups of process parameters based on orthogonal experimental design. The influence of process parameters on the surface damage was investigated. The results show that the surface cracks usually form at the mould outlet, which results from the inhomogeneous metal flow and the partial overheating. Pressure-keeping time is the dominant parameter for controlling the surface quality. Surface damage can be effectively avoided by optimizing the process parameters. The simulated values basicly accord with the experiment results.