Alumina abrasive grains mediated grinding induced glass surface and fractal analysis of SiO2 glass. (18th June 2021)

• Record Type: Journal Article
• Authors: Rasheed, I Abdul; Paul, Swati; Chhabra, Inder Mohan; Gupta, Mahender Kumar; Manimaran, P; Balasubramanian, Karthikeyan
• Is Part Of: Engineering research express. Volume 3:Number 2(2021)
• Publication Date: 2021-06-18
• Subjects: Al2O3 abrasives -- grinding -- lapping -- surface topography -- coherence correlation interferometer (CCI) -- sub surface damage (SSD) -- fractal analysis; Engineering -- Periodicals; 620.005
• DOI: 10.1088/2631-8695/ac09da
• Languages: English
• ISSNs: 2631-8695

Abstract

Abstract: Fabrication of optical components such as passive optics (mirrors, prisms, lenses) or active optics (polarizer's, laser gain media, adaptive optics) starts from a bulk material and reaches to the required size and shape. To achieve the required specification of the component, a series of process has to be followed from grinding to polishing stage. Initially, in grinding stage, material removal is faster, with more surface damage and less geometric control. During polishing stage, material removal is slower, with no surface damage but with greater geometric control. Hence, to achieve good surface quality, the component or work piece has to be controlled from grinding stage. We present an advanced surface and fractal analysis study on fused silica samples processed with different grit sizes such as 3, 5, 12, and 25 μ m aluminium oxide (Al2 O3 ) abrasives. The maximum sub surface damage (SSD) with respect to size of the abrasive grain ranged between 30 μ m to 5 μ m in empirical module. In theoretical module it varied from 45 μ m to 5.4 μ m for fused silica glass, mediated with loose abrasive aluminium oxide powder of 25 μ m and 3 μ m respectively. An experimental investigation is reported on the increasing effect of Al2 O3 grit sizes on the surface topography such as average roughness (Ra), which varied from 57 nm to 847 nm for 3 μ m and 25 μ m Al2 O3 abrasives respectively. Three-dimensional image analysis was captured through Phase Shift Interferometry (PSI) and Coherence Correlation Interferometer (CCI) technique. Field Emission Scanning Electron Microscope (FESEM) technique was utilized to characterize the Al2 O3 powders and the processed fused silica samples. Later, the images have been analysed using two-dimensional multifractal detrended fluctuation analysis (2D-MFDFA) to understand and confirm the multiple fractal nature on fused silica samples caused by varying grit size of Al2 O3 abrasives.