Optimized process for the fabrication of zirconia micro parts

A process and its parameters are proposed for fabrication of zirconia micro parts. In the process, UV lithography of SU-8 and replication of polydimethylsiloxane (PDMS) are used for the fabrication of the moulds. The PDMS moulds are filled with the zirconia slurry followed by drying, demoulding and sintering. In preparation of zirconia suspension, stability is controlled by adjusting pH with and without the presence of dispersant. The optimum pH and dispersant concentrations are determined with the aid of zeta potential, shrinkage and density. Through the characterization of physical properties, an improvement has been observed in the density and shrinkage of the resultant micro parts. It is found that the suspension stability, the density and the shrinkage are highly relative to the dispersant concentration. The optimal parameters have been achieved at pH 7; amount of dispersant = 13.4 mg/g of zirconia powder; solid loading = 078 vol.%. After sintering at 1650 °C for 2 h, shape retention of high quality zirconia micro parts have been achieved with a near fully density of (99% TD) and a linear shrinkage of 20.2% using the optimal parameters.