Additive manufacturing of zirconia parts by indirect selective laser sintering

Thermally induced phase separation (TIPS) was used to produce spherical polypropylene–zirconia composite powder for selective laser sintering (SLS). The influence of the composition of the composite starting powder and the SLS parameters on the density and strength of the composite SLS parts was investigated, allowing realizing SLS parts with a relative density of 36%. Pressure infiltration (PI) and warm isostatic pressing (WIPing) were applied to increase the green density of the ZrO2–PP SLSed parts. Infiltrating the SLS parts with an aqueous 30 vol.% ZrO2 suspension allowed to increase the sintered density from 32 to 54%. WIPing (135 °C and 64 MPa) of the SLS and SLS/infiltrated complex shape green polymer–ceramic composite parts prior to debinding and sintering allowed raising the sintered density of the 3 mol Y2O3 stabilized ZrO2 parts to 92 and 85%, respectively.