Paper Title
Roll Mold Patterning Technology for Lubrication Function of Cold-Rolled Steel Sheet

Abstract
Surface texturing technology has been actively developed to improve the strength, friction reduction and workability of steel sheet. The surface texturing of the steel sheet is performed by patterning the surface of the cold-rolled roll with a specific roughness and transferring the pattern to the steel sheet through rolling. In this paper, describe non-contact laser patterning technique using nanosecond laser of chrome-plated cold rolling roll, surface roughness analysis and lubrication friction analysis through 3D profile of micro pattern. First, laser processing parameters were optimized to obtain a specific surface roughness. Secondly, using the commercial numerical analysis program, the shape of the pattern performed on parameter simulation including the size, width, and depth. Based on simulation result, developed the lubrication friction-reduction pattern. The friction coefficient reduction effect could be expected when the simulation result pattern depth was 20㎛ or less. Finally, surface roughness of steel sheet is one of the key characteristic determining final appearances after painting. The functionality pattern was transcribed to the steel sheet through the rolling. The Ra parameters predict model was proposed from the transfer surface roughness ratio of steel plate measured. Keywords- Friction coefficient, Surface roughness, laser patterning, Roll, Lubrication.