RT Journal Article T1 Laser polishing of tool steel with CO2 laser and high-power diode laser A1 Ukar, E. A1 Lamikiz, A. A1 López de Lacalle, L. N. A1 del Pozo, D. A1 Arana, J. L. AB This paper presents the effect of the laser-polishing process applied to a milled and EDMed surface of DIN 1.2379 tool steel commonly used in the die and mold industry. The martensitic structure of this type of steel (showing hardness values up to 62 HRC) makes the polishing operation extremely difficult. At present polishing must be carried out manually by skilled workers, and this entails an expensive and prolonged process. An alternative to automation of the polishing process is a laser-polishing process, based on tightly controlled melting of a micro-layer of surface material which flows into and fills topographic valleys for a smoothed surface topography. Thus the main process parameters have been identified and optimized using two different types of industrial laser: a CO2 laser and a high-power diode laser (HPDL), obtaining up to 90% roughness reduction with mean roughness values (Ra) below 0.5 μm. Moreover, in order to secure a complete study of the process in accordance with the energy radiated, three-dimensional topographic surfaces were measured and a metallurgical study performed to determine the effect of laser radiation on the structure of the material. SN 0890-6955 YR 2010 FD 2010-01 LK https://hdl.handle.net/11556/3895 UL https://hdl.handle.net/11556/3895 LA eng NO Ukar , E , Lamikiz , A , López de Lacalle , L N , del Pozo , D & Arana , J L 2010 , ' Laser polishing of tool steel with CO 2 laser and high-power diode laser ' , International Journal of Machine Tools and Manufacture , vol. 50 , no. 1 , pp. 115-125 . https://doi.org/10.1016/j.ijmachtools.2009.09.003 DS TECNALIA Publications RD 28 jul 2024