PRODUCTION OF COMPOSITE SINTERED MACHINE PARTS

PROBLEM TO BE SOLVED: To remarkably increase the joining strength between the shaft part and the hole part by fitting the hole part of a member formed of a ferrous sintered alloy and the shaft part of a green compact obtd. by subjecting ferrous powder to compacting and making the amt. of the green compact to be thermally expanded in a high temp. region of the temp. equal to or above the specified one by making the thermal expansion of the green compact larger than the thermal expansion of of the sintered member. SOLUTION: A member (external member) with a hole part formed of a ferrous sintered alloy and a green compact (internal member) with a shaft part obtd. by subjecting ferrous alloy powder or a powdery mixture to compacting are integrally sintered in a state in which the hole part and the shaft part are fitted. At this time, the green compact having a compsn. by which the amt. to be thermally expanded in a high temp. region of >=750 deg.C in a sintering stage is made higher than that of the external member is used as the internal member. Moreover, the difference in the fitting dimensions between the hole part of the external member and the shaft part of the internal member is controlled to