Abstract
Laser bending is a forming process exploiting thermal stress introduced by laser scanning, and the process parameters include laser power, beam diameter, scanning speed and repetition number of scans. In this study, AZ31 magnesium alloy sheets were successfully bent by the laser irradiation, irrespective of the smaller temperature gradient originating from their high thermal conductivity, low melting point and low formability, although high laser power and low travelling speed result in the formation of cracks in the upper side of the sheets. It was found, furthermore, that crack-free laser bending is possible if laser absorbent is painted and the bottom side is cooled, because larger temperature gradient between both sides of the sheets can be achieved.