Three Phase Boundary Enhancement in SOFC Anodes by Applying Laser Drilling Technique

Laser drilling is one of the promising techniques to modify layers, but the interaction of composite materials with the laser radiation is non-trivial and hardly predictable. In this work, the experimental study of laser processing, that was applied to enhance porosity and thereby the length of three-phase boundary of plasma-sprayed YSZ-NiO-Ni cermet layer, is presented. For a better understanding of radiation interaction with composite materials the drilling was accomplished with different laser irradiation doses (1.57-4.210 5 J/cm 2 ) with two different laser systems. The diameter and shape of the laser drilled holes were analyzed with a scanning electron microscope (SEM) while changes of the elemental composition of the spatter versus conditions of irradiation were defined by energy dispersive X-ray analysis (EDX). It has been found that geometrical dimensions of the drilled holes as well as composition of the spatter vary non-monotonously with the laser irradiation dose. The threshold values of the laser irradiation dose for the optimal diameter of holes are reported.