SiC-bonded diamond materials produced by pressureless silicon infiltration

Extremely hard, wear-resistant SiC-bonded diamond materials with diamond contents of approximately 45% to 60% by volume can be prepared by pressureless infiltration of shaped diamond compacts with silicon. Components with large dimensions can be produced as graded or ungraded materials. Graded components are composed of Si-infiltrated SiC base materials with diamond-SiC composite layers of 0.1 mm to several mm in thickness in regions with high loading. This creates the possibility of producing low-cost, wear-resistant components of various geometries and dimensions with bending strengths of 400-500 MPa, hardness values of 48 GPa, and fracture toughness levels of 4.5-5 MPa∙m1/2 for use in extreme wear conditions. Thermal conductivities of up to 500 W/mK were obtained, render these materials interesting for heat sinks.