Study on the preparation process and properties of carbon fiber–reinforced ceramic mold shells

Abstract This study delved into the impacts of carbon fibers on process parameters such as the fluidity of the slurry, the thickness of the ceramic mold shell, and the drying time during the preparation of ceramic mold shells. Additionally, it explored the action mechanisms of carbon fibers on the flexural strength and corner strength of the mold shells. The findings indicated that carbon fibers caused a reduction in the fluidity of the slurry and an increase in its kinematic viscosity. Consequently, the single‐layer thickness of the mold shell increased, and the drying time was prolonged. Moreover, whether in the green body state or the sintered state, the flexural strength and corner strength of the mold shells were improved with the addition of carbon fibers. Regarding the fracture behavior, the primary failure mode of carbon fiber–reinforced ceramic mold shells was fiber pull out. During the pull out process, the debonding at the interface between the fibers and the ceramic matrix, along with the frictional slip after debonding, was the main way of energy dissipation for interface failure. The strengthening effect of carbon fibers on the mold shells was mainly realized through the bridging effect formed with the matrix.