Development of production technology and approbation of a new nitrogen- and carbon-containing precursor based on vanadium and aluminum for smelting a V – Al – N – C master alloy

A technology for obtaining complex nitrogen- and carbon-containing precursor materials V(51 – 43) – Al(30 – 36) – N(13,4 – 16,4) – C(2,7 – 6,0) was developed and tested on an experimental scale by nitriding by the method of self-propagating high-temperature synthesis of mixtures of V(65 – 50) – Al master alloys powders with graphite. The ratio of nitrogen to carbon in precursors can be varied over a wide range — N/C = 5.5 – 2.2. Using X-ray phase analysis, it was found that nitrogen in these materials is in the form of AlN and VN nitrides, and carbon is in the form of V2C, VC and V2Al0.96C1.1 carbides. The possibility of replacing graphite in the charge of out-of-furnace aluminothermal smelting of the V – Al – N – C master alloy with an alternative precursor V(51) – Al(30) – N(15) – C(2.7) has been experimentally confirmed. Using the methods of X-ray phase analysis, electron microscopy, and X-ray spectral microanalysis, it was found that the smelted using this precursor V – Al – N – C master alloy ingot is identical in phase composition and in distribution uniformity of nitride and carbide inclusions to alloy ingots that were smelted using other carbon-containing materials. The content of nitrogen, carbon and oxygen in the ingot meet the requirements of the technical specifications for V – Al – N – C master alloy.