混合润滑状态下表面粗糙度对拉深摩擦系数的影响

INFLUENCE OF SURFACE ROUGHNESS ON FRICTION COEFFICIENT IN DEEP DRAWING PROCESSES UNDER MIXED-FILM LUBRICATION

本文利用带料弯曲拉伸试验机、扫描电镜和表面轮廓仪等设备，探讨了模具和板材的表面粗糙度对拉深摩擦系数和工件表面质量的影响，同时研究了模具表面粗糙度对板材表面形貌的影响，磨擦系数与润滑剂粘度、拉深速度、板材表面粗糙度的三维全图关系，以及模具和板材的表面粗糙度对摩擦系数的协同作用效果．结果表明：提高润滑剂粘度和拉探速度，以及适当地提高板材表面粗糙度有利于降低磨擦，但增大模具表面粗糙度或模具与板材的表面粗糙度同时增大会加剧摩擦磨损．

The influence of the surface roughnesses of die and metal sheet on friction coefficient and surface quality of workpieces in deep drawing processes by means of Strip Bend- drawing Tester, SEM and contouopgh was investigated. The effect of die surface roughness on sheet surface roughness, and the three dimensional space diagram of frication coefficient-lubricant viscosity×drawing velocity-sheet surface roughness, as well as the synergism effect of surface roughnesses of die and sheet on friction coefficient were discussed in detail. The test results showed that increasing lubricant viscosity and drawing velocity and sheet surface roughness within limits were beneficial to decreasing friction coefficient. But increasing the surface roughness of die and sheet driultaneously may increase friotiod and wear.