为了实现单晶硅反射镜高效低损伤的超精密加工, 研究了基于工件旋转法磨削原理的单晶硅反射镜超精密磨削工艺。通过形貌检测和成份测试的方法分析了该工艺采用的超细粒度金刚石砂轮的组织结构特征, 并对单晶硅进行了超精密磨削试验, 研究了超细粒度金刚石砂轮的磨削性能。通过砂轮主轴角度与工件面形之间的数学关系实现对磨削工件面形的控制。最后, 采用超细粒度金刚石砂轮对Φ100 mm×5 mm的单晶硅反射镜进行了超精密磨削试验验证。试验结果表明, 超细粒度金刚石砂轮磨削后的单晶硅表面粗糙度Ra值小于10 nm, 亚表面损伤深度小于100 nm, 磨削后的单晶硅反射镜面形PV值从初始的8.1 μm减小到1.5 μm。由此说明采用该工艺磨削单晶硅反射镜能够高效地获得低损伤表面和高精度面形。

An ultra-precision grinding process employing a rotational grinding technique was investigated to achieve high-efficiency, low-damage grinding of monocrystalline silicon reflectors. First, the characteristics of ultra-fine wheels, such as their surface topography and compositions, were analyzed. The grinding performance of wheels was studied based on the grinding of monocrystalline silicon. Then, the shape of the grinding surface was controlled based on the mathematical relationship between the posture angles of the grinding wheel spindle and surface profile of the workpiece. Ultra-precision grinding experiments on Φ100 mm × 5 mm silicon reflectors with ultra-fine diamond wheels are conducted for verification. The results show that the surface roughness Ra is less than 10 nm, the subsurface damage depth is less than 100 nm, and the PV value of the surface of the silicon reflector decreases from 8.1 μm to 1.5 μm. It can be concluded that the grinding process can efficiently produce silicon reflectors with low surface damage and shapes of high precision.