Impact of wear parameters on NiCr-WC10Co4Cr and WC10Co4Cr HVOF sprayed composite coatings using response surface methodology
Abstract
In the present paper, experimental and statistical studies of wear behavior of two HVOF sprayed coatings (NiCr-WC10Co4Cr (Coat1) and WC10Co4Cr (Coat2)) deposited on 304L austenitic stainless steel have been investigated. Applied load, sliding velocity, and distance are the most important parameters that directly affect the wear volume of a given coating. In order to quantify the influence of each parameter on the wear rate of both coatings, two different loads (5 and 15 N), velocities (5 and 20 cm/s), and distances (500 and 1500 m) are selected to perform the experimental study. The microstructural study conducted on both coatings using scanning electron microscopy (SEM) and X-ray diffraction (XRD) technique reveals a dissolution of WC particles into the NiCr matrix with the formation of W2C eutectic phase that affects the coatings during tribology tests. The wear mecanism appears to be abrasive for Coat2 and combined mechanism of adhesive and abrasive wears in the case of Coat1. Based on the mathematical model developed using response surface methodology (RSM), the results show that both coatings yield the same response in terms of RSM individual output. In addition, RSM reveals that the normal load is the most significant individual parameter afecting wear volume with t-ratio of 46.11 and 32.00 of Coat1 and Coat2, respectively. However, the interaction of parameters is different regarding the nature of the coating. Normal load-sliding velocity interaction is the most influencing in Coat1, while Coat2 wear behavior is more influenced by sliding distance-normal load interaction