TWI Industrial Member Report Summary 204/1983
By P J Oakley
A series of transformation hardening trials have been carried out on a medium carbon steel using a defocused beam from a 2kW fast axial flow laser. The effect of laser power, beam diameter, traverse speed, beam absorption coating and focusing configuration were assessed. Tests were also made to examine the reproducibility of hardening. Although the trends in the morphology of the hardened regions were predictable, a variation in the microstructure of these regions was observed that could not be related to the laser processing parameters. The effect of different beam absorption coating thicknesses is postulated as the cause of this variation in microstructure.