High speed steels (often abbreviated HSS) are ferrous based alloys of the Fe–C–X multicomponent system where X represents a group of alloying elements comprising mainly Cr, W or Mo, V, and Co. These steels are mainly used for cutting tools, since they are characterized by their capacity to retain a high level of hardness while cutting metals at high speed. Generally, the X component is present in excess of 7%, along with more than 0.60% carbon.
Titanium aluminium nitride (TiAlN) or aluminium titanium nitride (AlTiN; for aluminium contents higher than 50%) is a group of metastable hard coatings consisting of nitrogen and the metallic elements aluminium and titanium. This compound as well as similar compounds(such as TiN and TiCN) are most notably used for coating machine tools such and endmills and drills to change their properties, such as increased thermal stability and/or wear resistance. Four important compositions (metal content 100 wt.%) are deposited in industrial scale by physical vapor deposition methods: