采用机械钻铣轻量化技术的轻型镜研制

以φ400mm轻型平面镜为例，介绍了采用机械减重法制造轻型镜的工艺技术。镜坯的轻量化采用了刚度虽不是最优，但工艺性最好的圆孔结构，并采用专门设计的钻头钻孔，再用氢氟酸消除微裂纹。加工结果表明，该镜的减重比达44．5％，但仍具有足够的刚度，且没有影响加工精度的变形。

Development of lightweight mirror with lightening techniques by mechanical drilling and milling

With a f400mm lightweight plane mirror as an example, a process and technology for manufacturing lightweight mirror by using mechanical lightening method is presented. A circular hole structure with better stiffness and the best manufacturability is adapted in lightening of mirror blank. The circular holes are drilled by the special-designed drill head and the micro-cracks are eliminated by hydrofluoric acid. The processing results show that the plane mirror still has enough stiffness even if its lightening ratio is as high as 44.5%, and there is no deformation that will affect processing accuracy.