METHOD FOR MANUFACTURING SINTERED STRUCTURAL PARTS HAVING HIGH DIMENSIONAL ACCURACY, AND APPARATUS THEREFOR

摘要

PROBLEM TO BE SOLVED: To solve such a problem that sintered structural parts can not acquire sufficient dimensional accuracy in a longitudinal direction, even though the sintered parts are repressed between an upper punch and a lower punch of a die in order to correct the dimension, after a precursor powder in the die has been vertically compression molded between the upper punch and the lower punch and has been sintered, because the accuracy is affected by rigidity of a press or the die as well as the positioning accuracy (error) of both punches in repressing. SOLUTION: This manufacturing method comprises forming the upper punch 30 so as to have a larger diameter than that of a compact to be sintered (the diameter of a flange for the compact having the flange), and sandwiching a positioning member 32 with a predetermined dimension between the upper punch and the die 10, to make a bottom dead point of the upper punch precisely constant and thereby enhance dimensional accuracy. COPYRIGHT: (C)2003,JPO