Correlation of Power Spectral Density with surface Quality of Fused Silica during Lapping and Polishing Process

Abstract

Glassy materials has its application in various systems including electronics and semiconductors and optics. Particularly, in optics lens magnifications are produced by Lapping and Polishing process. These methods are used surface modification of fused silica by various indenters. In our work, alumina spheres are used as indenters. Load and stress graphs were plotted based on simulation results and were compared with literature. Studies for Total deformation and Equivalentstress at various indenters’ size and loading pressures are carried out. It was observed that indenter sizes plays a vital role in cracks growth during lapping process. Minimizing subsurface damage (SSD) is in high demand for optics during grinding, lapping, and polishing. This study inspects and measures the SSD of fused silica developed in lapping. A series of simulations is conducted to reveal the influence of lapping parameters on SSD depth, including alumina size, lapping pressure. Results indicate that SSD depth are mostly sensitive to alumina size and lapping pressure.Indentation test is simulated using Finite Element Method based on contact mechanics approach. The relationship between load and indentation depth is obtained. The numerical results show goodagreement with experimental data. It is shown that FEM is an effective tool for simulation of indentation tests of optics