模具表面形态演化对冲压件表面损伤的影响

The Effect of Changing of Tool Surface Micro-Geometry on Surface Galling in Sheet Metal Forming

实验研究了高强度钢板成形过程中模具表面形态的演化规律及其对冲压件表面损伤的影响.高强钢冲压件采用带拉深筋的盒形件拉深工艺完成,使用Ry值评价模具表面粗糙度和零件表面损伤,借助光学显微镜观察零件表面损伤微观形貌.结果表明:随着盒形件拉深次数的增加,模具表面的Ry值不断增加,且只有在凹模圆角处发生增长,模具法兰的Ry值没有明显变化,同时冲压件表面损伤不断加剧,表面损伤萌生位置发生在盒形件圆角处;另外,模具硬度越小,模具表面Ry值增长速度越快,冲压件越容易产生表面损伤.

In high strength forming tests were carried and its effect on surface ga steel （HSS） sheet forming, out to study the changing lling of parts. The HSS sta with draw beads. The roughness value Ry is use ing of parts. The optical microscope is used to o at the tool corner positi flange of both die and b heavier surface galling. surface galling of tool surface m to eva is a highly concerned problem. Sheet micro-geometry m stampmg process ped parts are formed in the box deep drawing tools luate tool surface micro-geometry and surface gallserve micro-geometry. The test results reveal that the R on becomes larger with incrcasing inder almost keeps constant ： lowe of the forming numbers, in contrast the Ry at th r tool hardness leads to higher tool surface Ry an