Optimization of the manufacturing process of a tungsten-free hard alloy by spark plasma sintering of powders obtained by electro-erosive dispersion of TN20 alloy waste in alcohol

The purpose of this work was to optimize the conditions of spark plasma sintering of powders obtained by electrodispersion of metal waste of the TN20 alloy for the production of nonporous and high-hardness tungsten-free hard alloys. Methods. Dispersible metal waste is made up of 20x20x5 mm pieces of TN20 alloy. The chemical composition in accordance with GOST 26530-85 is as follows: Ni up to 15%; Mo up to 6%; Nb up to 0.1%; TiC the rest. The working fluid is isopropyl alcohol. The plant for metal waste dispersion is an experimental and patented one. The modes for dispersing metal waste are 61.5 UF (capacity), 130 V (voltage), at 130 Hz (pulse frequency). Powder fusion plant ‒ SPS 25-10 "Thermal Technology". The BVTS microstructure was studied using a scanning electron microscope QUANTA 600 FEG. Optimization of the conditions of spark plasma fusion of powders obtained by electrodispersion of metal waste of the TN20 alloy for the production of porous and high-hardness tungsten-free hard alloys was carried out using a factor experiment and the method of steep ascent by Box and Wilson. Results. In accordance with the goal set, aimed at optimizing the conditions of spark plasma sintering of powders obtained by electrodispersing metal waste from a TN20 alloy for the production of nonporous and high-hardness tungsten-free hard alloys, an optimal hardness of 95.2 HRA was established at the following values of factors: temperature 1250 °C, pressure 40 MPa, holding time 15 minutes. Conclusion. Thus, the goal has been achieved. The results of the work can find practical application in the organization of resource-saving and import-substituting technologies.