Fusion and viscosity of molten high-vanadium steels investigation with the aim of perfecting the powder obtaining from liquid state by sputtering

Manufacture of new brands of tool steel by means of powder metallurgy technique has been mastered in Ukraine. High-alloy steels powder is obtained by sputtering liquid metal stream getting out of a batcher through the exhaust outlet of 6 mm in diameter. The average yield of suitable powder makes 60-65%. The reason for the low yield of suitable powder is blocking the exhaust outlet with solid phase and stopping the pouring. The fusion characteristics and viscosity of these steels melts have been studied to work out the rational modes of high-alloy steels sputtering. Experimental researches of the tool steels technological properties have been performed on thermal analysis installation. It has been stated, that the liquidus tem-perature is the range from 1307-1463С, and the solidus temperature is the range from 1255-1436С. Experimental data we used and the formulas for calculation of liquidus temperature depending on the chemical composition have been obtained. The viscosity of the vanadium-containing steel Р0М2СФ10-МП melts has been determined by the method of damped torsional oscillations registration and by the capillary way as well. The melted steel temperature was taken both in the crucible of the induction furnace and in the iron receiver in the course of sputtering under production conditions. The recommendations as to the high-alloy steels sputtering have been developed and introduced in production making it possible to increase the suitable powder yield on the average of 10%