Thermodynamic and kinetic study on interfacial reaction and diamond graphitization of Cu—Fe-based diamond composite

Abstract

Cu–Fe based diamond composites used for saw-blade segments are directly fabricated by vacuum and pressure assisted sintering. The carbide forming elements Cr and Ti are added to improve interfacial bonding between diamond and the Cu–Fe matrix. The interfacial reactions between diamond/graphite and Cr or Ti, and diamond graphitization are investigated by thermodynamics/kinetics analyses and experimental methods. The results show that interfacial reactions and graphitization of diamond can automatically proceed thermodynamically. The Cr<sub>3</sub>C<sub>2</sub>, Cr<sub>7</sub>C<sub>3</sub>, Cr<sub>23</sub>C<sub>6</sub>, and TiC are formed at the interfaces of composites by reactions between diamond and Cr or Ti; diamond graphitization does not occur because of the kinetic difficulty at 1093 K under the pressure of 13 MPa