Taguchi analysis of single layer CrN coatings on AISI 304 Stainless Steel to study its erosive corrosive wear behaviour

The purpose of present study was to investigate the erosive corrosive wear behavior of single layer (CrN) coatings on AISI 304 Stainless Steel samples with varying coating thickness (0-200 nm) in the range of 50 nm. The slurry jet erosive test was conducted on Slurry Jet Erosion Tester in saline slurry (3.5wt% salt) under the different working conditions with varying impact velocity (10-25 m/s), impingement angle (30°-75°) and erodent discharge (160-280 gm/min). Taguchi analysis was applied to find optimum parameters for the minimization of erosion rate of various coated and uncoated samples. The results of Taguchi experiments also indicated that among all the factors, impact velocity became least significant when samples were coated with CrN whereas it was most significant for uncoated samples. Coating thickness was the second most significant factor in the case of CrN coated samples. PVD- CrN coatings reduced the wear rate by nearly 2 times.