基于定制表面的材料流动控制研究

Research on material flow control based on tailored surface

为解决板料体积成形工艺中因应力应变状态在不同区域的差异化分布易导致材料流动不合理而影响产品质量的问题,提出采用定制表面进行材料流动控制。分别对模具和坯料定制表面展开研究,通过在模具上设置微特征以及在坯料表面进行喷丸处理达到控制材料流动的目的。为分析定制表面控制材料流动的规律及机理,设置不同的微特征结构参数及喷丸工艺参数,基于凸台挤压测试探究了不同形貌的定制表面对材料流动的控制能力及其摩擦学性能。结果表明:喷丸能提高材料的表面粗糙度及表面硬度,从而导致材料流动阻力增大;模具微特征定制表面对材料流动的阻碍效果受到流动路径和模具储料能力的协同影响;对比两种定制表面,模具微特征对材料流动的阻碍作用比坯料喷丸更为显著。

To solve the problem that in sheet bulk metal forming process,the locally differential distribution of stress and strain states can easily lead to unreasonable material flow which affects product quality,tailored surface was proposed for material flow control.Research on the tailored surfaces of mold and blank was carried out.The purpose of controlling the material flow was achieved by setting microfeatures on the mold and blasting the blank surface.To analyze the law and mechanism of tailored surfaces controlling material flow,different microfeatures structure parameters and blasting process parameters were set.Based on the pin extrusion test,the ability of tailored surfaces with different morphologies to control material flow and their tribological properties were explored.The results show that the surface roughness and surface hardness of the material can be improved by blasting,which leads to the increase of flow resistance of the material.The blocking effect of mold tailored surface with microfeatures on material flow is collaboratively influenced by the flow path and mold storage capacity.Comparing the two kinds of tailored surfaces,the blocking effect of mold with microfeatures on material flow is more significant than that of blasting blank.