FORFARANDE FOR FRAMSTELLNING AV ETT VARMSMITT MATERIAL AV PULVER

摘要

A method for producing a powder forged material comprising 1.4 DIFFERENCE 3.5% Si, 0.2 DIFFERENCE 0.9% Mn and 1.0 DIFFERENCE 2.0% C by weight, the remainder substantially consisting of iron is provided herein. This method consists in (a) pulverizing the swarf of an FCD cast iron mother material and separating and removing graphite microparticles from the mother material to produce a powder body of said mother material having a carbon content of 1.0 DIFFERENCE 2.5%; (b) preforming the powder body having the reduced carbon content to a density lower than that of the mother material and applying a lubricant to the preformed body; (c) heating the preformed body at a temperature above the melting point of the mother material but below 1300 DEG C. in a non-carburizing atmosphere and then cooling the preformed body until the temperature of the body is lowered to 1000 DEG DIFFERENCE 1100 DEG C. and forging the preformed body in a dye so that the specific gravity is the same or slightly higher than that of the mother material and, finally, (d) subjecting the forged body to a diffusion treatment by heating it above the austenitizing temperature. The present invention also relates to forged materials produced by this method.