Research on properties and microstructure of TiB₂/(Cu, Ni) interpenetrating phase composites by melt infiltration

TiB₂/(Cu, Ni) interpenetrating phase composites (IPCs) with ceramic content of 75%-86% are prepared by high-temperature powder sintering and subsequently melt infiltration. The microstructure and mechanical properties of the TiB₂/(Cu, Ni) IPCs with different TiB₂ ceramic volume contents are investigated detailedly. The phase constitution and microstructures are studied by SEM and XRD. The bending strength and fracture toughness are also investigated by three-point bending tests. The results show that high temperature sintering of pre-pressed compact combined with subsequently melt infiltration is a good way to fabricate TiB₂/(Cu, Ni) interpenetrating phase composites. Mechanical properties and densities are improved observably. The bending strength and fracture toughness attain 640.5 MPa and 9.37 MPa o m^1/2, and the relative density reaches 98.4% with the infiltration temperature of 1500° and the ceramic volume content of 81.6%.