Solidification microstructures in the rapidly solidified powder of high alloyed V–Cr tool steel

The article deals with the solidification microstructures of the rapidly solidified powder of 3% C–3% Cr–12% V (wt.%) hypereutectic iron alloy Ch3F12 (C3Cr3V12). Five different solidification microstructures were classified in powder particles: microstructure with eutectic spherulites, microstructure with eutectic colonies without primary carbides, microstructure with the primary carbides in the centers of eutectic colonies, microstructure with star-like carbides and microstructure with dispersed globular carbides. Light microscopy, scanning electron microscopy and transmission electron microscopy were used for experimental observations. X-ray diffraction analysis proved the presence of M4C3 carbide, austenite and indicated the presence of M7C3 carbides. The chemical composition of primary carbide phase was determined by energy-dispersive X-ray analysis.