Preparation of low-cost high strength soluble ceramic cores using heavy calcium carbonate by binder jetting and vacuum impregnation

Binder jetting method was used for printing ceramic green body using heavy calcium carbonate (HCC) processed from dolomite consisting of CaMg(CO3)2 as raw material, and the nano-ZrO2 dispersion was used to vacuum impregnate the ceramic green body. After sintering, the low-cost high strength soluble ceramic core was obtained. The CaO generated after the decomposition of the HCC reacted with the ZrO2 at high temperature to form CaZrO3. This reaction reduced the porosity of the ceramic core, thereby improving its bending strength by 317.6%. The CaZrO3 formed made the sintered ceramic core have certain hydration resistance due to the insolubility of the CaZrO3, extending the use time of the ceramic core. The CaO and MgO generated after the decomposition of the HCC also ensured the good solubility of the ceramic core. This study provides a new method for the preparation of the low-cost high strength soluble ceramic cores by additive manufacturing method.