Titanium nitride with silicon additions for tribological applications

Abstract

AbstractMicrostructure and mechanical properties of duplex treated system with (Ti,Si)N coating on nitrided stainless steel were investigated. The (Ti,Si)N coatings with the thickness of 1 µm were deposited on nitrided 316L stainless steel substrate by reactive single target magnetron sputtering. The stainless steel was glow discharge nitrided at 450 °C temperature. The transmission electron microscopy (TEM) showed that the coatings were built of heavily defected fine columnar crystallites. The adherence of the coatings to their substrates was examined by scratch test. The highest hardness was measured for the coatings obtained from TiSi4 target (4 at.% Si) and reached maximum of 23 GPa and 27 GPa on not nitrided and nitrided steel respectively. The tribological behaviors of the duplex system were studied in ball‐on‐disc friction test. The (Ti,Si)N coating on nitrided steel exhibited better tribological properties than the nitrided steel without any coating and coating on not nitrided steel. The (Ti,Si)N coatings presented low friction coefficient (0,1–0,2) up to the coating failure. The nitrided steel and duplex system with (Ti,Si)N coating showed essential wear reduction as compared with 316L steel. The observed improvement in coating micromechanical properties with increasing silicon additions is a direct result of their higher hardness caused by grain refinement and more dislocated microstructure. Copyright © 2010 John Wiley & Sons, Ltd.