Effects of femtosecond laser surface texturing on mechanical properties and low temperature degradation of alumina toughened zirconia

The mechanical properties and low temperature degradation of 20 wt% alumina toughened 3 mol% yttria stabilized zirconia (ATZ) subjected to femtosecond laser surface texturing were evaluated. A directional fracture behavior accompanied by a significant reduction (>50%) of the biaxial flexural strength of the laser textured materials was observed for the investigated laser processing parameters. The directional fracture behavior was determined by both the direction of the laser induced thermal cracks and the loading condition during biaxial bending testing. The aging resistance of the laser surface textured ATZ was similar to that of the as-sintered group, indicating femtosecond laser texturing did not affect the aging performance of the material. Laser texturing of pre-sintered ATZ followed by sintering is a promising approach to alleviate the negative impact of laser texturing on the mechanical properties of the material. The flexural strength of the material obtained by this approach was increased to more than 700 MPa as compared to around 530 MPa for laser texturing of sintered ATZ, which was still much lower than that of the as-sintered group (1040 MPa).