Synthetic or natural diamond grits are affixed to the functional parts of the tool by bonding materials. The hardness, strength, high wear resistance and low coefficient of friction of diamond make it ideal for cutting, drilling, grinding and polishing. Metal powders are used in both metal bonded and resin bonded diamond tools.
Metal bonded tools are produced using powder metallurgy (PM) technology to achieve the desired shape and strength. The composition of the metallic powder matrix is critical in holding the diamond in place and in wearing at a rate compatible with the diamond loss during use. As the metallic powders wear down then new diamond is exposed at the surface thereby maintaining the cutting or abrading surface. Bond strength is dictated by the alloy mix of the matrix and the amount of compaction and heat applied during the PM process. Examples of use are diamond saw blades, diamond core drill bits and grinding wheels. Areas of application range from dentistry to road construction.
Resin bonded tools are produced by mixing diamond grit with resin powder and fillers such as copper powder. The mixture is then pressed, cured and machined. Polishing pads and grinding wheels are typical examples of resin bonded diamond tools.