A cermet is a cemented carbide with titanium based hard particles. The name
cermet combines the words ceramic and metal. Originally, cermets were composites of TiC and nickel. Modern cermets are nickel-free and have a designed structure of titanium carbonitride Ti(C,N) core particles, a second hard phase of (Ti,Nb,W)(C,N) and a W-rich cobalt binder.
Ti(C,N) adds wear resistance to the grade, the second hard phase increases the plastic deformation resistance, and the amount of cobalt controls the toughness.
In comparison to cemented carbide, cermet has improved wear resistance and
reduced smearing tendencies. On the other hand, it also has lower compressive strength and inferior thermal shock resistance. Cermets can also be PVD coated for improved wear resistance.
Cermet grades are used in smearing applications where built-up edge is a problem. Its self-sharpening wear pattern keeps cutting forces low even after long periods in cut. In finishing operations, this enables a long tool life and close tolerances, and results in shiny surfaces.
Typical applications are finishing in stainless steels, nodular cast irons, low carbon steels and ferritic steels. Cermets can also be applied for trouble shooting in all ferrous materials.
- Use low feed and depth of cut.
- Change the insert edge when flank wear reaches 0.3 mm.
- Avoid thermal cracks and fractures by machining without coolant.
GC1525 Tough coated cermet grade for interrupted cuts, turning.
CT5015 Wear resistant cermet grade for continuous cuts, turning.
CT530 Milling grade for shiny surfaces.
CT525 Parting and grooving grade for finishing.