<?xml version="1.0" encoding="UTF-8"?><rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:dcq="http://purl.org/dc/terms/"><records count="1" morepages="false" start="1" end="1"><record rownumber="1"><dc:product_type>Journal Article</dc:product_type><dc:title>Grinding of silicon carbide for optical surface fabrication, Part 1:				surface analysis</dc:title><dc:creator>Shanmugam, Prithiviraj; Lambropoulos, John C.; Davies, Matthew A</dc:creator><dc:corporate_author/><dc:editor/><dc:description>This paper presents a study of the grinding of three different grades					of silicon carbide (SiC) under the same conditions. Surface topography					is analyzed using coherent scanning interferometry and scanning					electron microscopy. The study provides a baseline understanding of					the process mechanics and targets effective selection of process					parameters for grinding SiC optics with near optical level surface					roughness, thus reducing the need for post-polishing. Samples are					raster and spiral ground on conventional precision machines with metal					and copper-resin bonded wheels under rough, medium, and finish					grinding conditions. Material microstructure and grinding conditions					affect attainable surface roughness. Local surface roughness of less					than 3 nm RMS was attained in both chemical vapor deposition (CVD) and					chemical vapor composite (CVC) SiC. The tool footprint is suitable for					sub-aperture machining of a large freeform optics possibly without the					need for surface finish correction by post-polishing. Subsurface					damage will be assessed in Part 2 of this paper series.</dc:description><dc:publisher/><dc:date>2022-01-01</dc:date><dc:nsf_par_id>10429827</dc:nsf_par_id><dc:journal_name>Applied Optics</dc:journal_name><dc:journal_volume>61</dc:journal_volume><dc:journal_issue>15</dc:journal_issue><dc:page_range_or_elocation>4579</dc:page_range_or_elocation><dc:issn>1559-128X</dc:issn><dc:isbn/><dc:doi>https://doi.org/10.1364/AO.455863</dc:doi><dcq:identifierAwardId>1822049; 1822026</dcq:identifierAwardId><dc:subject/><dc:version_number/><dc:location/><dc:rights/><dc:institution/><dc:sponsoring_org>National Science Foundation</dc:sponsoring_org></record></records></rdf:RDF>