Effect of processing parameters on the laser glazing of plasma-sprayed alumina-titania ceramic

An Nd-YAG laser beam has been employed to glaze the surface layer of atmosp heric plasma-sprayed alumina-titania (AT) ceramic composite deposited on a low carbon steel substrate. The effect of laser processing parameters such as power intensity, traverse speed, and beam focussing distance on microstr ucture and processing defects have been evaluated. Experimental study yield ed a shiny glazed surface of plasma-sprayed AT ceramic composite by choosin g an appropriate range of parameters. The working range of process paramete rs is illustrated. XRD analysis has been carried out for determining possib le phase changes with different processing parameters. XRD analysis showed that there was only marginal variation in the phase change when glazing wit h parameters within the working range. Monitoring of AE was observed to clo sely indicate the response of the ceramic to the glazing process. (C) 2001 Elsevier Science B.V. All rights reserved.