Laser micromachining of zirconia (Y-TZP) ceramics in the picosecond regime and the impact on material strength

The capabilities of a high average power picosecond laser are assessed for micromachining yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) in its hard state. Laser machining of this material presents an attractive alternative to conventional machining techniques when precision customized parts are required due to the difficulty in machining Y-TZP in its hard state. Compared with previous nanosecond work the picosecond laser enables similar micromachining to be carried out at the same rate but with a superior surface finish and with no evidence of surface cracking. Strength measurements have been carried out using a four-point bend test rig and confirm that the improvement in surface quality translates to higher strength in machined components. © 2009 The American Ceramic Society.