EXCIMER-LASER ABLATION OF AL2O3-TIC CERAMICS - LASER-INDUCED MODIFICATIONS OF SURFACE-TOPOGRAPHY AND STRUCTURE

Samples of an Al2O3-34 wt% TiC ceramic were processed with KrF excimer laser radiation (248 nm), using a fluence in the range 2 to 8 J/cm(2) . The roughness and the ablation rate vary considerably with increasin g number of pulses, reaching a constant value at > 200 pulses. In stat ionary regime, they both increase when fluence increases. Laser proces sing results on the formation of a globular topography recast layer by a selective ablation process, alumina being rapidly laser sputtered b y an electronic mechanism, while titanium carbide is thermally ablated . (C) 1998 Elsevier Science B.V.