Colloidal forming of macroporous calcium pyrophosphate bioceramics in 3D-printed molds.

A technique for colloidal forming of CaPO macroporous bioceramics, based on low-pressure injection molding (LPIM) of a glycerol-water slip containing CaPO and Ca(НPO) into a plastic mold fabricated via FDM 3D-printing, was proposed. Chemical reaction between the solid phases of the water containing slip - CaPO and Ca(НPO), resulting in brushite (CaHPO·2HO) formation, led to consolidation of the casting and preserved its complex architecture in the course of mold burning-out. Macroporous ceramics of Kelvin structure (70% macropores with the sizes from 2 up to 4 mm), based on a pre-defined composition with 10 wt% Ca(PO) and sintered in liquid-phase regime, demonstrated a compressive strength of 1.