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Abstract

in clude high-alloyed white cast irons, high-speed steels (hSSs), highentropy alloys (hEAs), cold-formed die steels, cemented carbide alloys, particle-reinforced metal matrix composites (PMMCs), etc. [7][8][9][10]. A wide range of conventional and innovative technologies are focused to modify a working surface via structural and chemical modi fication as well as coating deposition to create protecting layers of up to several millimetres thick [11][12][13]. however, in many applications, the wearinduced volume loss is much bigger; thus, the parts should be manufactured from special materials ensuring higher bulk wear resistance. the increased requirements for wear-resistant materials imply using non-standard solutions when creating new types of tribological alloys. Multicomponent Cast Ironsone of the relatively new classes of wear-resistant alloys is 'multicomponent cast irons' (MCCIs), which were first proposed by Matsubara with coauthors [14,15] in the mid-1990s to increase the durability of rolls of hot rolling mills. the idea of MCCIs followed the known concept of alloying high-speed steel M2 (AStM A600), which implies the addition of several carbide-forming elements in approximately equal proportions (M2 steel contains 0.78-0.88 wt.% C, 5.50-6.75 wt.% W, 4.50-5.50 wt.% Mo, 3.75-4.50 wt.% Cr, and 1.75-2.20 wt.% V). A basic chemical composition of MCCI is (in wt.%) fe-2 C-5 Cr-5 Mo-5 W-5 V-5 Co [16]. Molybdenum and tungsten (which act similarly) are adopted in MCCIs to form complex carbides (Mo, W, fe) 2 C or M 2 C, and (Mo, W, fe) 6 C or M 6 C, where M denotes a metal (martensite). being dissolved in matrix, Mo and W improve the hardenability and promote the secondary precipitation hardening under tempering (which is important for hot temperature wear applications). Vanadium forms hard eutectic carbides (V, fe)C or (V, fe) 4 C 3 (denoted as MC); also, it takes part in secondary hardening. Chromium is partially dissolved in matrix inhibiting pearlite and bainite transformations, thus, enhancing the hardenability. In addition, Cr contributes to wear resistance through eutectic carbide M 7 C 3 , which is harder than cementite carbide. In their turn, carbides M 2 C, M 6 C, and MC are harder than M 7 C 3 . Cobalt decreases the hardenability but it greatly improves the high-temperature strength suppressing the heat-induced grain coarsening. thus, MCCIs feature a multiphase structure consisting of different hard carbides dispersed in the metallic matrix.the main feature which distinguishes MCCIs from M2-hSS is about two-fold increased carbon content (1.8-2.2 wt.%) [17]. Carbon concentration controls the crystallization path and the set of carbide phases in MCCIs. According to [18], carbon content is selected based on C bal