高速轧制工作界面表面形貌对混合润滑状态下冷轧过程的影响

摘要

The analytical model of cold rolling in the mixed lubrication regime was established based on the average Reynolds equation,Peklenik surface pattern parameter theory and the bulk plastic deformation theory under the condition of mixed lubrication.The film thickness and friction factors varying with speed and reduction based on the impact of surface topography and the interface pressure and the fractional contact area varying with the position of the work zone based on various surface topography and reductions were analyzed in mixed lubrication.The results show that film thickness decreases as the reduction increases for all asperity orientations of surface roughness.The oil film thickness reaches its maximum when the surface roughness is in transverse asperity lay and reaches its minimum when the surface roughness is in longitudinal asperity lay.For the same reduction,the oil film thickness gets the smallest film thickness increment when the surface roughness is in transverse asperity lay and gets the largest film thickness increment when the surface roughness is in longitudinal asperity lay due to the increasing non-dimensional speed; friction has the highest factor in longitudinal asperity lay and the lowest in transverse asperity lay and friction is between the highest and the lowest in isotropic asperity lay; the higher reduction rate exhibits higher friction factor.In transverse asperity lay,the interface pressure distributions are much flatter.%根据平均Reynolds方程、Peklenik表面模式参数理论和混合润滑条件下大体积塑性变形理论,建立混合润滑状态下冷轧板带分析模型.系统分析混合润滑状态下,基于工作界面表面形貌,工作界面油膜厚度、摩擦因素随速度和压下率变化的情况；以及基于不同的压下率和表面形貌,界面压力、接触面积随工作区位置变化的情况.分析结果表明:在表面粗糙度所有排列方式中,油膜厚度随着压下率增大而下降,表面粗糙度横向排列产生最高的油膜厚度,表面粗糙度纵向排列产生最低油膜厚度.对于同样的压下率,随着界面无量纲速度的增大,表面粗糙度横向排列有最小的油膜厚度增量,表面粗糙度纵向排列产生最大的油膜厚度增量；表面粗糙度纵向排列下的摩擦因数最大,横向排列下的摩擦因数最小,各向同性排列介于两者之间；压下率越高,摩擦因数越高.表面粗糙度横向排列情况下,界面应力的分布要平缓得多.