Tailoring layered Csf/SiBCN composites with pseudoplastic fracture behavior: Strengthening and toughening mechanisms

The layering process using phenolic resin coupled with pressureless sintering technique was explored to prepare short carbon fiber-reinforced SiBCN composites (C sf /SiBCN). The effect of phenolic resin content on the microstructure and mechanical properties of C sf /SiBCN was mainly studied. Results suggest that the addition of phenolic resin can appropriately improve density and flexural strength and reduce total pore volume of the composites because phenolic resin can partly consolidate SiBCN powders to promote shaping via low-temperature pressureless sintering. As the phenolic resin content increases, the fracture behavior changes from delamination fracture to monolithic fracture, thereby reducing fracture displacement. The reason for this performance is that the interlayer bonding is enhanced to hinder crack propagation along the layers.