Hard WС–(Ті,W)C–10Со Alloy with Increased Hardness and Strength

Abstract

Some characteristics are reported for modified hard alloy T5K10 formed under the conditions of purposeful control over the thermokinetic free vacuum sintering parameters minimizing the processes of solid- and liquid-phase interaction between tungsten carbide and cobalt, which determine the redistribution and recrystallization of carbide grains. The synthesized WС–(Ті,W)C–10Со hard alloy is characterized by a homogeneous finely grained structure, a high density (ρ = 12.98 g/cm³), a low level of residual microporosity, a bimodal composition of WC grains, and bridges between carbide grains. As compared to the commercial analogue, the synthesized hard alloy has a 2.4 GPa higher hardness (Н_V = 15), a 270 MPa higher mechanical bending strength, a 1.4 MPa m^0.5 higher fracture toughness, and 1.5 times higher wear resistance. The modification of sintering technology and structural transformations in the synthesized WС–(Ті,W)C–10Со hard alloy have result in a 2.5-fold increase in its service durability during rough steel turning (forged axles of a railway wagons platform) and, in the case of deep soil chiseling, an increase in abrasion resistance is 48%.