start-ver=1.4 cd-journal=joma no-vol=68 cd-vols= no-issue=1 article-no= start-page=197 end-page=200 dt-received= dt-revised= dt-accepted= dt-pub-year=2019 dt-pub=20191231 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=High surface quality micro machining of monocrystalline diamond by picosecond pulsed laser en-subtitle= kn-subtitle= en-abstract= kn-abstract=In micro machining of monocrystalline diamond by pulsed laser, unique processing characteristics appeared only under a few ten picosecond pulse duration and a certain overlap rate of laser shot. Cracks mostly propagate in parallel direction to top surface of workpiece, although the laser beam axis is perpendicular to the surface. This processed area can keep diamond structure, and its surface roughness is smaller than R-a = 0.2 mu M. New laser micro machining method to keep diamond structure and small surface roughness is proposed. This method can contribute to reduce the polishing process in micro machining of diamond. (C) 2019 Published by Elsevier Ltd on behalf of CIRP. en-copyright= kn-copyright= en-aut-name=OkamotoY. en-aut-sei=Okamoto en-aut-mei=Y. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=OkadaA. en-aut-sei=Okada en-aut-mei=A. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=KajitaniA. en-aut-sei=Kajitani en-aut-mei=A. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=ShinonagaT. en-aut-sei=Shinonaga en-aut-mei=T. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= affil-num=1 en-affil=Graduate School of Natural Science & Technology, Okayama University kn-affil= affil-num=2 en-affil=Graduate School of Natural Science & Technology, Okayama University kn-affil= affil-num=3 en-affil=Graduate School of Natural Science & Technology, Okayama University kn-affil= affil-num=4 en-affil=Graduate School of Natural Science & Technology, Okayama University kn-affil= en-keyword=Laser beam machining (LBM) kn-keyword=Laser beam machining (LBM) en-keyword=Laser micro machining kn-keyword=Laser micro machining en-keyword=Diamond kn-keyword=Diamond END