METHOD FOR MANUFACTURING CYLINDRICAL MEMBER WITH COATED INNER SURFACE

PROBLEM TO BE SOLVED: To provide technology for forming a coating of a self-fluxing alloy having a high surface hardness on the inner circumferential surface of a cylindrical member body. SOLUTION: After horizontally placing cylindrical member body 1, a self-fluxing alloy powder in an amount corresponding to a thickness of coating is disposed on the inside of the cylindrical member equally in its axial direction. Then, the cylindrical member body 1 is rotated at high speed to form a powder layer with a uniform thickness on the inner circumferential surface. After that, the cylindrical member body 1 is heated to melt the powder therein and to form a molten metal layer, which is later cooled and solidified to form a coating a coating on the inner surface. When the self-fluxing alloy is melted and solidified, an atmospheric pressure of 0.3-3 MPa is applied on the surface of the molten metal layer located on the inner circumferential surface of the cylindrical member body 1 and the rotation speed of the cylindrical member body is controlled so as to generate a centrifugal force of not less than 10G on the inner circumferential surface, so that the surface harness of the coating on the inner surface can be increased, while preventing the occurrence of pinholes. COPYRIGHT: (C)2006,JPO&NCIPI