单晶硅曲面镜低损伤精密磨削及检测技术研究

发布时间：2018-06-04 22:18

本文选题：单晶硅曲面 + 精密磨削　；参考：《国防科学技术大学》2015年硕士论文

【摘要】：单晶硅曲面光学元件在高能激光系统中具有重要作用,其加工的面形精度和损伤性能对系统的性能有较大影响。单晶硅曲面工件成形加工过程存在许多问题有待解决,而成熟的单晶硅平面镜的加工工艺并不适用于曲面成形。单晶硅又是典型的硬脆材料,普通磨削加工不能有效控制工件的亚表面损伤,使得后续的抛光工艺难以权衡加工效率、成本与最终加工精度之间的关系,因此需要将精密磨削作为普通磨削与抛光工艺之间的衔接。本文围绕误差源对曲面面形精度的影响和工艺参数对工件亚表面损伤的影响两个方面进行研究,以期解决单晶硅曲面工件加工过程中损伤抑制与面形精度提升的问题。研究主要内容包括:(1)基于精密延性域磨削机理,分析单晶硅材料脆塑转变磨削特性,得到临界磨削力、临界切深和砂轮的最小转速等参数值,为后续工艺参数优选提供依据。(2)研究影响单晶硅曲面工件成形精度的因素。通过建立对刀误差、砂轮磨损对加工精度的影响模型,得到对刀误差的误差形式和砂轮磨损规律,提出具体的中心对准原则和磨损补偿的迭代磨削的工艺路线。(3)研究曲面磨削过程亚表面缺陷的分布规律。通过工艺实验,建立磨削力、亚表面缺陷深度与加工工艺参数之间的关系,得到抑制缺陷的最优加工参数。(4)以直径195mm单晶硅凸抛物面为对象,进行加工实验。搭建在位测量平台并对其测量性能进行评价。根据在位测量结果,提出合理的补偿加工方案,最终加工工件表面粗糙度Ra值为0.081μm,面形精度PV值为3.77μm,亚表面缺陷深度约为3~5μm。
[Abstract]:Single crystal silicon curved surface optical element plays an important role in high energy laser system. The surface shape accuracy and damage performance of the single crystal silicon surface optical element have great influence on the performance of the system. There are many problems to be solved in the forming process of monocrystalline silicon surface workpiece, but the mature machining process of single crystal silicon plane mirror is not suitable for surface forming. Monocrystalline silicon is a typical hard and brittle material. Common grinding can not effectively control the sub-surface damage of workpiece, which makes it difficult for the subsequent polishing process to weigh the relationship between machining efficiency, cost and final machining precision. Therefore, it is necessary to use precision grinding as the link between common grinding and polishing technology. In this paper, the effect of error source on surface shape accuracy and the effect of process parameters on subsurface damage of workpiece are studied in order to solve the problems of damage suppression and improvement of surface precision during machining of monocrystalline silicon surface workpiece. The main research contents include: (1) based on the precision ductility domain grinding mechanism, the characteristics of brittle plastic transition grinding of monocrystalline silicon materials are analyzed, and the critical grinding force, critical cutting depth and the minimum rotational speed of grinding wheel are obtained. The factors that affect the forming accuracy of monocrystalline silicon curved workpiece are studied. By establishing the model of tool alignment error and grinding wheel wear on machining accuracy, the error form of tool alignment error and grinding wheel wear rule are obtained. The principle of center alignment and the process route of iterative grinding for wear compensation are put forward to study the distribution of subsurface defects in the surface grinding process. The relationship between grinding force, depth of subsurface defects and machining process parameters was established through technological experiments. The optimum machining parameters for restraining defects were obtained. The processing experiments were carried out with diameter 195mm monocrystalline silicon convex paraboloid as the object. The measurement platform is built and its measurement performance is evaluated. According to the in-situ measurement results, a reasonable compensation processing scheme is proposed. The final workpiece surface roughness Ra value is 0.081 渭 m, the surface shape precision PV value is 3.77 渭 m, and the subsurface defect depth is about 3 渭 m.
【学位授予单位】：国防科学技术大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ127.2

【参考文献】