Spark plasma sintering of B4C-TiB2 composite: effect of combustion synthesized nanoparticle on sinterability and mechanical properties

Abstract

This study investigated the effects of fine particles with high surface area synthesized by Self-propagating High-Temperature Synthesis (SHS) on the SPS process and the properties of the resulting products. Correlations were established between particle size, SHS product addition, sinterability, and mechanical properties. The products were characterized by measuring shrinkage percentages, relative density, microhardness, elastic modulus, and fracture toughness, which were further correlated with SEM–EDS results. The results revealed that SHS nanoparticles significantly increased fracture toughness, especially with additions above 60%, by reducing average particle size, increasing powder porosity, and adding composite powder. The product exhibited high relative density (99.03%), elastic modulus (464 GPa), and fracture toughness (4.65 MPa.m1/2) when SPS was used on B4C-TiB2 powders containing 80% SHS product at a low temperature of 1550 °C. By adding 80% SHS product, hardness increased by 62% (19.5 GPa) and fracture toughness by 24%, even at low sintering temperatures, thus reducing energy consumption.