Hybrid TiSiN, CrC/C PVD coatings applied to cutting tools

A new development in cutting tools has been made for machining aluminum. Hybrid PVD coatings consisting of a super hard TiSiN base layer and a low friction CrCx/a-C:H top layer are used on cutting tools where the combination of low friction and resistance to abrasion is required. When machining aluminum silicon, CrCx/a-C:H resists the adhesion and galling of aluminum to the cutting tool by reducing friction and TiSiN strongly resists abrasive wear. s research, TiSiN films with a CrCx/C top layer have been produced in a hybrid cathodic arc/sputter physical vapor deposition system. Applied by cathodic arc plasma deposition, X-ray diffraction shows TiN changes from a (111) preferred orientation to (200) texture structure with silicon additions. When CrCx/C is subsequently deposited by sputtering, CrC XRD peaks are not found. The material is amorphous. ed by micro-indentation hardness tests, Si is shown to increase the hardness of TiSiN. When machining abrasive A390 aluminum, the wear resistance of taps coated with a TiSiN base layer and a low friction CrCx/C top layer is likewise improved with silicon additions to TiN. The CrCx/C top layer is shown to have frictional and wear characteristics similar to DLC coatings.