Characterization and modification of technical ceramics through laser surface engineering

This chapter is focused on the modification of technical grade ceramics through laser surface engineering. An experimental investigation was carried out to reveal the laser-ceramic interaction using a 1.075μm wavelength fiber laser on Si₃N₄ and ZrO₂ technical grade ceramics. Various aspects of laser-material interaction are demonstrated, namely, the topography; composition; microstructure; and mechanical, thermal, and internal properties as result of the laser surface treatment. The results showed considerable modification in the surface topography, surface finish, material removal, composition, and the fracture toughness parameters-K_1c of both the ZrO₂ and the Si₃N₄ technical ceramics. In addition, temperature distributions of the thermal energy during laser surface treatment enabled the prediction of various phase changes. Such findings and characterization methods employed in combination will not only enable one to better understand the effects of the laser-ceramic interaction, but will also contribute to the development of the laser surface treatment process.