Precise micromachining of yttria-tetragonal zirconia polycrystal ceramic using 532 nm nanosecond laser

High quality micro-sized steps and blind hole structures without microcracks, chips or spatter deposition were machined on yttria-tetragonal zirconia polycrystal (Y-TZP, 3 mol% yttria) by nanosecond laser (wavelength=532 nm, pulse width similar to 6 ns). The diameter of blind hole is 500 pm and each step is 500 10 pm wide and 100 +/- 5 pm deep. The 1.35 mm(3)/min removal rate and the smooth machined surface with Ra=2.824 pm roughness depicting the high precise and efficient processing were achieved. The ablation characteristics of nanosecond laser process of Y-TZP ceramic were also studied. Based on the study, a reasonable design of the processing path for micromachining of a finer embedded step with 24 +/- 2 mu m width (smaller than the 60 pm focused spot size) around the inner-wall of a 2 x 2 mm(2) cavity was developed. These results and discussion offer new possibilities in the manufacturing of bio-ceramic products by nanosecond laser with high processing quality and efficient. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.