粉体压制过程密度变化机理及影响因素模拟分析
Analysis on Numerical Simulation of Density Change Mechanism and Influencing Factors in Powder Compacting Process
蒋 卿1， 李 云1， 焦明华2， 王 兵1， 吴玉程1
点击：4078次 下载：0次
作者单位：1. 合肥工业大学 材料科学与工程学院，安徽 合肥 230009； 2. 合肥工业大学 摩擦学研究所，安徽 合肥 230009
中文关键字：粉末； 压制； 数值模拟； 位移滞后效应； 相对密度
英文关键字：powder； compact； numerical simulation； displacement lag effect； relative density
中文摘要：采用MSC.MARC有限元模拟软件对轴套粉体压制成形过程中粉末的位移走向和粉末位移对生坯相对密度的影响进行研究。同时，研究了不同模壁润滑条件以及不同厚度高度比对生坯密度分布的影响。结果表明,粉体成形过程中模壁摩擦导致的位移滞后效应决定了生坯最终的相对密度分布状况；粉末的位移变化规律与生坯的密度分布相似。随着模壁润滑条件的改善和高度厚度比的增加，生坯的密度分布均匀性得到提高；尤其是采用特殊润滑时，生坯密度均匀性得到了明显的改善。这些为研究粉体压制致密化过程提供了理论参考依据。
英文摘要：The displacement direction of powder and the influence of powder's displacement on the green compact's relative density of shaft sleeve powder in the compacting process were simulated by MSC.MARC FEM analysis software. In the mean time, the influences of different lubrication condition of the die wall and different thickness-to-height ratio on the distribution of green compact's relative density were also studied. The results show that the relative density distribution of the green compact is determined by the displacement lag effect caused by the die wall friction in the compacting process; the change law of powder's displacement and the relative density distribution of the green compact in the compacting process are similar. The uniformity of the green compact's relative density improves with the improvement of lubrication condition and the increase of thickness-to-height ratio. Especially, the uniformity of the compacts' relative density obviously improves under special lubrication condition. This work can lay the theory foundation for the study of the powder densification process.