Abnormal sintering densification behavior of boron carbide formed by extrusion-based additive manufacturing

This study investigates the abnormal sintering behavior of boron carbide (B4C) formed by Extrusion-Based Additive Manufacturing (EAM) process, which possesses higher initial green density but exhibits lower sintered density compared to dry-pressed counterparts. XRD and SEM were utilized to investigate microstructure and lattice characteristic of the sintered B4C, and the lower sintered density of EAM-ed B4C was explained by the less strain energy stored in green body than that in dry-pressed sample. This finding offers direct evidence that residual strain energy may outweigh green density in governing the sintering densification behavior of B4C.