ISO - M :

Stainless steels are materials alloyed with a minimum of 12% chromium; other alloys may include nickel and molybdenum. Different conditions, such as ferritic, martensitic, austenitic and austenitic-ferritic (duplex), create a large family. A commonality among all these types is that the cutting edges are exposed to a great deal of heat, notch wear and built-up edge. Group M includes austenitic stainless steels, austenitic/ferritic steels and cast steels, manganese steel, alloy cast iron, malleable iron. The group is subdivided into the application groups 01-40, dependent on the cutting load.

ISO - K:

Cast iron is, contrary to steel, a short-chipping type of material. Grey cast irons (GCI) and malleable cast irons (MCI) are quite easy to machine, while nodular cast irons (NCI), compact cast irons (CGI) and austempered cast irons (ADI) are more difficult. All cast irons contain SiC, which is very abrasive to the cutting edge. Group K incorporates all forms of grey cast iron and malleable cast iron. Dependent on cutting load it is subdivided into the application groups 01-40.

ISO - N :

Non-ferrous metals are softer metals, such as aluminum, copper, brass etc. Aluminum with an Si-content of 13% is very abrasive. Generally high cutting speeds and long tool life can be expected for inserts with sharp edges. This group includes non-ferrous metals, especially aluminum-alloys and non-metal materials. It is, depending on the cutting load, divided into the application groups 01-30.