采用基于扫描白光干涉原理的三维表面轮廓仪对粒度为3000的金刚石砂轮表面形貌进行测量,其图像拼接功能可以确保较高的横向分辨率、较高的垂直分辨率和较大的取样面积。利用频谱分析方法对砂轮表面的频率构成进行分析,通过理想的低通数字滤波消除测量仪器引起的系统噪声和砂轮表面的高频分量,然后重建砂轮表面的三维形貌,在此基础上得出砂轮的磨粒出刃高度、静态有效磨粒密度、磨粒平均间距。研究表明,采用细粒度金刚石砂轮进行超精密磨削时,磨粒出刃高度大体上服从正态分布,静态有效磨粒密度远低于理论磨粒密度,真正起切削作用的磨粒数量极少。
A 3D surface profiler based on scanning white light interferometry is introduced to measure the surface topography of a 3 000 mesh diamond grinding wheel, and a large sampling area could be achieved by its image stitching capability without compromising lateral or vertical resolution. Fourier analysis is performed to identify the frequency structure of the wheel's surface topography, and then the characteristics of diamond grains are extracted by digital filtering. The protrusion height distribution of diamond grains, the static effective grain density and the distribution of inter-grain spacing of the grinding wheel are derived. The study shows that the grain protrusion height obeys an approximate normal distribution, the static effective grain density is much lower than the theoretical grain density, and only a small number of diamond grains are effective in grinding process with fine diamond grinding wheel.