Evaluation of mechanical properties of Ti(Cr)SiC(O)N coated cemented carbide tools

In order to enhance the life of cemented carbide tools for milling Ti6Al4V alloy, Ti(Cr)SiC(O)N (including TiSiCN, TiSiCON, CrSiCN and CrSiCON) coatings were deposited on flat samples for characterization and K40UF cemented carbide end-mills for milling tests. The adherence strength of the coatings was determined using scratch tests. Wear tests were carried out using a ball-on-disk tribometer with Ti64 balls without lubricant. Dry milling tests of the coated end-mills were carried out on the Ti64 alloy at a 45 m/min cutting speed. The results indicated that the Cr-based coatings (CrSiCN and CrSiCON) have a better adherence strength and toughness than the Ti-based coatings (TiSiCN and TiSiCON). The CrSiCN and CrSiCON coatings had a lower friction coefficient than the TiSiCN and TiSiCON coatings, while the TiSiCN and TiSiCON coatings had a lower wear rate than the CrSiCN and CrSiCON coatings. The milling test results showed that TiSiCN and CrSiCN coated tools had a better cutting performance than TiSiCON and CrSiCON coated ones.

► Ti(Cr)SiC(O)N coatings have been fabricated by PEMS.
► The TiSiCON coating with oxygen has better adherence than TiSiCN without oxygen.
►  The Cr-based coatings have better adherence and toughness than the Ti-based one.
► The TiSiCN and CrSiCN coated tools show superior performance in dry milling Ti64.