磨削加工表面粗糙度理论模型修正方法

大多数计算磨削表面粗糙度的理论公式都是基于砂轮表面磨粒与工件表面的几何创成机理建立的.理论公式虽然计算精度较高,但由于对一些磨削条件的简化,特别是假定工件表面全部由切削过程完成而忽略了材料的塑性隆起变形对表面粗糙度的影响,使其计算结果往往小于实际表面粗糙度数值.分析了磨削加工表面塑性隆起对轮廓最大谷底高度的影响,提出了计算磨削表面粗糙度数值的塑性影响系数及其理论修正公式,并给出了理论计算与实验结果.

Modification for Theoretical Model of Ground Surface Roughness

Most of the theoretic formulas to calculate the ground surface roughness are based on the geometrically generating interaction between grits and workpiece surface. Because of some simplifications especially the premise that the ground surface is formed completely just by cutting process, the effect of plastic upheaval deformation of workpiece surface on surface roughness is overlooked so as to cause the theoretic value of surface roughness to be often smaller than the real value. Analyzes the effect of plastic upheaval deformation on the maximum depth of the valley bottom of roughness profile and gives the plastic coefficients and modifies theoretical formulas of ground surface roughness. Compared with testing results, the calculated results by the formulas involving plastic coefficients are proved more accurate.