Abstract: Eight metal-bonded diamond tooling materials are fabricated to evaluate the performance of coated diamonds in different metal matrices. The contribution of coatings to transverse rupture strength is assessed through three-point bending tests. Coupled with SEM and EDS analyses, the bonding between diamonds and metal matrix is revealed. The effects of coatings to the wear performance of diamond segments are studied through circular sawing of granite and in-process monitoring of cutting forces and power in sawing. It is found that the coatings are positive to the increased retention of bond matrix to diamonds. It is difficult to establish a specific relationship between the wear performance of the specimens and their transverse rupture strength if the bond system is different. However, the bonding among bond matrix components contributes more than the bonding between the bond matrix and diamonds. The performance of coatings depends not only on whether the matrix contains rare earth but also on the types of bond matrix.

Key words: Coated diamond, Retention, Sawing, Transverse rupture strength