Abstract
In this study, an attempt is made to improve the tribological properties of austenitic 201 stainless steel by coating with TiN via physical vapor deposition followed by cathodic cage plasma nitriding (CCPN) under optimum conditions. The outcomes of TiN coating and CCPN treatment were examined individually as well in order to find the optimal method of producing corrosion-free surface coatings. The base and coated coupons were analyzed for structural, morphological and mechanical changes by performing Vickers micro-hardness analysis, X-ray diffraction analysis, wear track analysis and SEM and AFM analyses. The CCPN treatment of TiN-coated coupons resulted in significantly higher hardness and stability than the base and TiN-coated coupons. The linear polarization resistance (LPR) of base, TiN-coated and CCPN-coated coupons was measured about 141, 356 and 558 k ohm.cm(2), respectively. LPR of CCPN-coated coupons was four times higher than that of the base coupon. The high LPR of CCPN-coated coupons demonstrates their superior stability and performance in harsh environments. CCPN-treated coupons had the lowest wear rate, corrosion rate and wear volume among all the tested coupons. These findings reveal that CCPN treatment of TiN-coated coupons is a more appropriate method of enhancing surface hardness, wear resistance and corrosion resistance.