| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for producing a metal forged product, which improves the mechanical properties, leaves no burr removal mark in the forged product, uses a cylindrical material having a surface layer on the circumferential surface thereof for labor saving in the process, and is suitable for enhancing the yield of the material relative to a forging material. <P>SOLUTION: The method for producing a metal forged product having a plurality of branches includes: a preliminary forging step of forming a preform by closed forging from a cylindrical material having a surface layer on a circumferential surface thereof such that the surface layer 302 is contained in a surface region of the preform; and an intermediate forging step of subjecting the preform to forging to thereby extrude the surface layer in the form of burr outside a periphery of a forged product. <P>COPYRIGHT: (C)2012,JPO&INPIT |
