High temperature tribological behaviour of TiSiN(Ag) films deposited by HiPIMS in DOMS mode

Self-lubricant coatings offer an opportunity to increase tool lives in dry machining operations for hard-to-cut materials. In this work, TiSiN(Ag) coatings were deposited to assess the influence of silver in the tribological behaviour at high temperatures. Two types of counterparts were used: 6 mm diameter Al2O3 and TiAl6V4 balls. RT tests conducted against Al2O3 balls showed that silver slightly decreases the friction but deteriorates the wear resistance. Wear resistance is improved when the temperature is increased to 600 degrees C, when compared to RT tests. Tribology tests against TiAl6V4 balls showed that silver has a beneficial effect in the reduction of friction and wear. Additionally, silver hinders the adhesion of material to the wear track. Temperature also plays an important role in propelling the effects of silver.