高精度光学表面磁流变修形

Magnetorheological finishing for high-precision optical surface

系统研究了确定性磁流变抛光高精度光学表面的关键技术及应用。介绍了自行研制的KDMRF-1000F磁流变抛光机床及其基本工作原理,给出了抛光过程中建立材料去除模型的两种方法和如何根据驻留时间完成路经规划的过程。采用KDMRF-1000F磁流变抛光机床和KDMRW-1水基磁流变抛光液对直径80mm的K4材料平面反射镜和直径145mm的K9材料球面反射镜进行修形实验。实验显示,样件一面形收敛到PV值55.3nm,RMS值5.5nm;样件二面形收敛到PV值40.5nm,RMS值5nm;样件的表面粗糙度均有显著改善。结果表明,磁流变修形技术具有高精度、高效率、高表面质量的特点。

A novel deterministic sub-aperture magnetically assisted polishing method, Magnetorheo- logical Finishing （MRF）, was explored and some fundamental principles and key problems in MRF process were researched. The KDMRF-1000F MRF polishing machine developed by our group was introduced and two methods to establish the material removing model in polishing process were given. Then, how to realize a path planning based on dewell time was described. By using the KDMRF-1000F MRF polishing machine and KDMRW-1 water based MR fluid, one K4 flat work piece （80 mm in di- ameter） and one K9 sphere work piece （145 mm in diameter） were polished,experiments show that work piece one has a peak-to-valley （PV） value of 55.3 nm and a root-mean-square （RMS） value of 5.5 nm; and work piece two has a PV value of 40.5 nm and a RMS of 5 nm,which indicates that the surface roughnesses of two work pieces have been improved obviously. It is concluded that the MRF has the abilities to produce optical surfaces with high form accuracy, surface roughnesses and high efficiencies.