In Vitro Corrosion and Wear Investigation of Multifunctional TiAlMoN Sputtered Coatings on Cold-Sprayed SS316L

Abstract

Although TiAlN has been thoroughly studied, there is still an ongoing demand for developing new-based TiAlN films with enhanced protection efficiency for a long lifetime and high load-bearing capability linked to friction and corrosion mechanisms. This work aims to present the effect of Mo content by studying the structural tribomechanical, wettability, and corrosion behaviors in TiAlMoN coatings deposited by magnetron sputtering on cold-sprayed stainless steel 316L substrates. TiAlMoN coatings showed a dense columnar structure with the coexistence of titanium and molybdenum nitrides, and TiN (200) preferred orientation changed to TiN(111) with increasing Mo content. The surface energy of the TiAlMoN coatings decreased gradually with the increase in Mo content. The TiAlMoN coating containing 16.09 atom % Mo possesses the highest hardness and Young's modulus (29.5 and 334.5 GPa, respectively) and the maximum H/E and H 3 /E 2 of 0.092 and 0.237, respectively. Formations of tribolayer oxides reduced the friction and enhanced the wear resistance of TiAlMoN coatings in atmospheric conditions and reached the minimum values of 0.3 and 0.849 × 10 −6 mm 3 /N, respectively, at 16.09 atom % of Mo under 5 N load charge. Corrosion examination in simulated seawater revealed that TiAlMoN coating-coated SS316L exhibited a significant positive shift of about −16 mV in corrosion potential with a notable reduction in corrosion current density (1.41 nA/cm 2 ), confirming the improved corrosion performance. The combination of both cold spray and magnetron sputtering techniques for producing this kind of component is shown to have great potential in processing applications.