METHOD FOR PRODUCING METAL POWDER MATERIAL Russian patent published in 1995 - IPC

FIELD: powder metallurgy. SUBSTANCE: initial blank is placed into scull crucible made of alloy BT 6 and subjected to heating by 1000 A, 42 V plasma jet in inert gas medium consisting of 80% of helium and 20% of argon purified of moisture and oxygen to 70 and 30 ppt respectively at a pressure of 0.1 to 0.15 MPa. Heating of melt in scull crucible is effected by plasma jet of main plasma generator, which is used for melting blank. Melt flowing from spout of crucible is introduced directly into plasma jet of second plasma generator operating at 550 A and 43 V. Jet overheated at last section is fed together with heat flow into granulating mill rotating with a speed of 6500 rpm. Blanks are fed into melting zone with the aid of pushers. For this purpose blanks are rigidly connected to pushers, which are made of the same alloy BT6. Blanks fed to melting zone shall be free of any projections or depressions. No cinder remains in crucible at the end of melting process. Granular powder yield is 98%. EFFECT: increased powder yield, minimized labour input into preparation of blanks.