Tribological studies on bearings coated with titanium carbo-nitride (TiCN) using chemical vapour deposition (Cvd) method

Abstract

The present work mainly focus on the development of a coating material for bearing applications using Chemical Vapour Deposition (CVD) method. The presence of coatings and surface topography play a vital role in the tribological performance of sliding components such as bearing. The coating used should reduce friction as well as wear of the components. An attempt has been made to develop a coating material that is provided on bearings in order to facilitate wear-resisting property improving the bearing properties significantly. Titanium Carbonitride TiCN is an extensively used material on tools used for abrasive cutting and machining operations, but still not used as a coating material in bearing applications. In this direction, (TiCN), an abrasion resistant ceramic coating was formed by adding a small amount of carbon to the Titanium Nitride (TiN) and the developed coating was applied on the bearings in the form of a thin film of 3 ?m thickness. The carbon makes the coating harder and thereby provides a lower friction coefficient. Specimens were developed as per ASTM standards with size 10 x 10 x 20mm with and without coating material. The coated specimens were tested on Pin-on-disc wear testing machine and a comparative study between the TiCN coated bearing and the conventional bearing was carried out in terms of wear rates determination. SEM and EDAX analysis was also carried out for the tested specimens to ensure proper distribution of carbon in TiN. From the study it was found that the coated material showed lesser wear rate by 21% when compared to the conventional uncoated specimen and SEM showed proper bonding between the carbon and TiN.