Metallurgical & Materials Engineering Congress of South-East Europe 2015 195 MICROSTRUCTURAL CHARACTERIZATION OF WC AND CrC BASED COATINGS APPLIED BY DIFFERENT PROCESSES G.M.Bakić 1 , V.Maksimović 2 , A.Maslarević 3 , M.B.Djukić 1 , B.Rajičić 1 , A. Djordjević 4 1 University of Belgrade, Fac. of Mechanical Engineering, Kraljice Marije 16, 11035 Belgrade, Serbia 2 Vinca Institute of Nuclear Sciences, University of Belgrade, PO Box 522, 11001 Belgrade, Serbia 3 IC Fac. of Mech. Engineering, University of Belgrade, Kraljice Marije 16, 11035 Belgrade, Serbia 4 Messer Tehnogas a.d., Batajnicki put 62, Belgrade, Serbia amaslarevic@mas.bg.ac.rs Abstract Numerous mechanical structures and assemblies have frequent outages because of wear of machine parts due to the effects of abrasion and erosion. There are several methods to protect parts from wear and one of them is by applying a protective coating on the endangered area. It is well known that the coatings with carbide distributed in a metallic matrix have an excellent wear resistance. In this paper characterization of three coatings were carried out: coating with tungsten carbide (WC) in NiBSiFe matrix, coating with chromium carbides (CrC) in FeNiSi matrix deposited by plasma transferred arc method (PTA), as well as, coating with WC carbide in CrNiBSi matrix deposited by oxy-acetylene thermal spray process. The above mentioned alloys, before application to the base material, were in a powder state. This paper describes applied coating technologies on a substrate - S235JR steel, powders characteristics, microstructure and properties of coatings, phase composition, and micro hardness of different microconstituents. Key words: PTA, tungsten carbide, chromium carbide, wear resistance Introduction Numerous mechanical structures and assemblies have frequent outages because of wear of machine parts due to the effects of abrasion and erosion. There are several methods to protect parts from wear and one of them is by applying a protective coating on the endangered area. It is well known that the coatings with carbide distributed in a metallic matrix have an excellent wear resistance [1,2]. Research has shown that abrasion resistance increase with an increase of carbon content in the matrix of metal. The composition of the matrix of metal also has a significant influence, therefore softer and ductile matrix have a higher impact resistance in comparison to the matrix that have a higher hardness and brittleness [3]. There are different methods of thermal spraying, as well as, welding methods which can be used in order to apply protective coatings onto different substrates