比较了蓝宝石不同晶面磨削特性的差异。对蓝宝石晶体的A面、C面、M面及R面开展精密磨削试验, 并从磨削力、磨削力比、比磨削能及表面形貌等角度比较了蓝宝石4个晶面磨削特性的差异。采用金刚石砂轮在精密平面磨床上对蓝宝石4个晶面进行磨削, 采用测力仪测量磨削过程中的磨削力, 并根据所测得的磨削力计算磨削力比和比磨削能。最后, 采用扫描电子显微镜观测工件磨削表面形貌。试验结果显示: 蓝宝石的4个晶面中C面的磨削力最大, 其次是M面和A面, R面的磨削力最小; 比磨削能亦为C面最大, 其次是M面和A面, R面的比磨削能最小; 磨削力比则是M面最大, 其次是A面和C面, R面的磨削力比最小。在相同磨削条件下, 蓝宝石不同晶面磨削材料的去除方式有所不同, A面、M面和R面主要以脆性断裂、破碎和解离方式去除为主, 且破碎坑较大, 表面相对较为粗糙; 而C面则存在部分脆性断裂和部分粉末化去除, 破碎坑较小, 表面相对平整。因此, 蓝宝石不同晶面的磨削特性差异明显, 其磨削力、磨削力比、比磨削能及材料去除方式均存在明显的不同。

The different grinding characteristics of different crystal faces of a sapphire were compared. A precision grinding test of A-plane, C-plane, M-plane and R-plane for the sapphire was carried out from the grinding force, grinding force ratio, specific grinding energy and surface topography to research their grinding characteristics. Four crystal faces of the sapphire were grinded by a diamond grinding wheel on a precision surface grinder. The grinding forces were measured by a dynamometer, and the grinding force ratio and the specific grinding energy were calculated according to the measured grinding forces. The surface morphology of a workpiece was observed by a scanning electron microscopy. The results indicate that the different faces of the sapphire have different grinding forces, and the C-plane shows the maximum value, followed by the M-plane, A-plane, and the R-plane. The size orders of specific grinding energy are the same as the grinding force. However, the maximum value of grinding force ratio is for the M-plane, followed that by the A-plane and C-plane, and the R-plane is the minimum one. Under the same grinding conditions, the different crystal faces have different grinding material removal modes. The A-plane, M-plane and R-plane are mainly based on brittle fracture, fragmentation and dissociation removal, the crushing pit is larger, and the surface is rough. The C-plane is mainly based on part of the brittle fracture and part of powder removal, the broken crater is smaller, and the surface is relatively smooth. As a results, since the A-plane, C-plane, M-plane and R-plane of the sapphire have different grinding characteristics, they show different grinding mechanisms, grinding forces, grinding force ratios, specific grinding energies and material removal modes.