Investigation of the solvent debinding in the injection molding of ZrO2 ceramics using LDEP, HDPE and wax binders

In this paper, zirconia green parts with the binder system containing low density polyethylene (LDPE) were prepared by injection molding. The green parts after solvent and thermal debinding were sintered at 1500 degrees C for 2 h. The influences of LDPE on solvent debinding were emphatically studied. A new method was proposed to determine the extracting degree of the wax binders in comparison with the common method. The results showed that the solvent removable binders could not be extracted completely during the solvent debinding though the replacement of HDPE with LDPE promoted this process. The extracting degree of the wax binders was about 74-80% and increased with the increase of LDPE contents. In addition, it was also found that microcracks easily occurred in the green parts after the solvent debinding when using LDPE replacing HDPE, which may result in the decrease of the bending strength of the sintered samples.