Research On Ultra-precision Turning About Contracted Sample Of The Shaft Of The Optical Collector

In lithography machining, the optical receiver with good performance and highefficiency of collection is necessary, and it is important to the next illumination system inorder to collect more photons. Currently, the most promising optical structure is grazingincidence mirror, which named Wolter-1. The replication method requires the outersurface of the mandrel and the inner surface of the mirror have the same structure andquality. But obtaining high-precision surface is very difficult, and related detectiontechnology restrict high quality surface. Therefore, this paper aims to machine themandrel which can meet the accuracy requirements, and researching on the ultra-precision single point diamond turning technology of the mandrel.In the linear interpolation model, using the method of straight line fitting with equalerror method to plan cutting tool path, and through the related theory planning tool pathfor UMAC spline interpolation mode of CNC system. To avoid interference between tooland the workpiece caused by an irrational trajectory planning in the actual processing, arcand B-spline smoothing the singular point at surface intersect have been provided in thispaper. Furthermore, tool path of ultra precision machining has been optimized by theradius compensation.NC program of rough machining has been generated by using MasterCAM, so thatit can shorten the processing time and improve processing efficiency. Furthermore, usingVERICUT software for precision turning simulation of different interpolation modes, andverifying the correctness of the tool path in order to avoid a collision interferencephenomenon occurs in the actual processing. According to the simulation results, it candirectly obtain the size range of overcut and residual on the workpiece surface afterturning. Finally, smoothed turning track and treatment effect have been observed.In the experiment, this paper realize ultra precision machining for the shaft ofoptical collecting system using ultra precision diamond lathe. Then detecting the surfacefigure accuracy by three coordinate measuring machine which has high precision.Compared with the surface figure accuracy of shaft between linear interpolation andspline interpolation mode, and analyzing the major factors which affecting the surface figure accuracy during machining. So the rationality and correctness of the theory in thisresearch could be verified.