摘要
以316L不锈钢为喂料的注射过程为研究对象,使用双流体模型模拟注射过程中坯体内粉末体积分数的分布,得到出现严重两相分离区域的直观三维分布图,并应用工业CT(industrial computed tomography)对模拟结果进行验证。结果表明:该方法可以得到注射成形零件中任意区域粉体的分布;注射试样在浇口的下方区域,以及模壁、顶点区域,易出现较严重的两相分离,导致后续的烧结过程中出现收缩不均匀,是应该重点关注的区域;随注射速率从30 cm3/s提高到90 cm3/s,两相分布合理区域的体积呈先增大后减小的趋势,在70 cm3/s时达到最大;模拟结果中粉末体积分数分布曲线的变化趋势和变化幅度都与CT检测结果相符,实验验证了模拟结果的可靠性。
The variation of powder volume fraction during powder injection molding filling flow process was simulated based on the two-fluid model. The region in which the serious separation between powders and binder occurs was visually observed in the three-dimensional distribution graph, and the industrial CT was used to verify the results. The results indicate that the simulating variation of powder volume fraction can be obtained with this method. The serious separation between powders and binder occurs in the region of die wall, vertex, and area below the inlet in the sample, leading to non-homogeneous shrinkage during sintering, and these regions need to pay more attentions. As the increase of the injection rate, the volume of low fluctuation region increases firstly, and reaches a maximum value when the injection rate is 70 cm3/s, then decreases. The change trend and fluctuation range of the distribution curves of powder volume fraction are fitted with the CT test results, so the reliability of simulating results is demonstrated.
出处
《粉末冶金材料科学与工程》
EI
北大核心
2013年第2期149-154,共6页
Materials Science and Engineering of Powder Metallurgy
基金
国家重点基础研究发展计划(973计划)资助项目(2011CB606306)
关键词
粉末注射成形
数值模拟
双流体模型
粉体分布
工业CT
powder injection molding
numerical simulation
two-fluid model
powder distribution
industrial CT
