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Thermal spraying is one of the most widely used techniques of surface treatment against wear and corrosion. Especially, flame spraying process due to its advantages, such as its being more economical, easier to implement and more adaptable to a wide range of materials. However, mechanical performances are not always satisfactory because of high porosity, cracks and weaker adhesion. To obtain hard wear and corrosion-resistant coatings, the most suitable materials are those like Nickel, Cobalt-based alloys, hardmetals and ceramics [1][2][3]. Because of their high melting points, ceramics are depositedin preference by plasma spraying technique, while the conventional flame and HVOF spraying techniques are used to deposit metals and hard metals materials. For many applications, Ni-based alloy is used to improve the performances of components whose surface is subjected to wear and/or corrosion. It can be also used to replace hard chrome coating which endangering human health and environment [4]. Many studies are reported on tribological properties of Ni-based coatings produced by thermal spray and laser cladding techniques [5][6][7][8][9]. Ni-based alloy with an amount of hard ceramic phase is reported as more advantageous than the metal material deposited alone. Tungsten carbide (WC) and chromium carbide Cr 3 C 2 [10] are the most commonly recommended phase reinforcement. Wear resistance is enhanced by Ni-based alloy and reinforced Ni-based alloy produced by thermal spraying process. To quantify the wear of coating, it is necessary to perform tests under conditions similar to those of the operative regime, but laboratory tests are commonly used as a quantitative tool to describe the wear behaviour of the material tested [11]. For this, a large number of tribological tests are available. The results of tribotest are strongly related not only to the characteristics of the materials couple, but also to the whole mechanical system and its environment. Consequently, selecting the most appropriate test for a specific objective is fundamental to making meaningful interpretations. Several studies have already exposed the tribological behaviour of the Nibased and composite coatings under different conditions, such as dry sliding [4,7,[12][13][14] AbstractNiCrBSi is a Ni-based alloy universally recognized for its superior mechanical properties, attributed to the presence of hard-dispersed carbides and borides, which is dependent on the deposition technique. Moreover, Metal Matrix Composites (MMC) materials will aim to combine the resilience of metals with high wear resistance specific of ceramics which made them innovative for a large wide of wear resistance applications. In this paper, thick NiCrBSi and NiCrBSi-WC coatings are made ontoS235JR mild steel substrates using an oxyacetylene flame-spraying torch (SuperJetEutalloy, Castolin Eutectic). Two different wear tests: sand/wheel wear test in dry conditions and the pin-on-disc wear test in continuous motion are used to investigate addition effects of WC reinforcing ceramic...

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