METHOD FOR CENTRIFUGAL INDUCTIVE COATING WITH POWDERY MATERIALS Russian patent published in 1994 - IPC

FIELD: powder metallurgy. SUBSTANCE: article has its cavity filled with powder before being placed at a spaced relation to the heat source and rotated on being simultaneously heated to the sintering temperature. The sintering of the article is accompanied by its transfer relative to the heat source. As the article is heated to the sintering point the heat source to article clearance is kept constant with the article additionally receding from the heat source along its radius to the following rule (experimental or estimated): l = U(T) = f(T). U(T) = shifting of the article surface points caused by thermal expansion vs. heating time with the relationship being defined by experimental or calculational means with allowance made for the temperature gradient along the depth of the article. T = outer surface temperature defined by experimental or calculational means with regard to nonlinearity of the assigned heat conductivity. The temperature is peculiar to the time at which the sintering point is achieved on the contact interposed between the inner surface of the article and the coating applied. At a period when the article is kept at the sintering temperature effected is additional radial relative drifting the article and the heat source apart which action at any time is determined by the time dependence of power with the latter being in its turn determined by the size of the clearance between the article and the heat source. EFFECT: lower energy consumption, higher quality of coating. 1 tbl, 6 dwg