PURPOSE: To permit production of a sintered body having excellent cold plastic workability by loading a high-silicon Al alloy powder contg. silicon at a specific ratio into a container provided with an Al alloy plate just before an extrusion die and sintering and extruding the powder under compression.
CONSTITUTION: After the Al or Al alloy plate 3 is set at a prescribed thickness into the extrusion container 2 in which the die 1 is set, the high SiAl alloy powder 4 contg. 13W30wt.% Si is loaded therein independently or after an additive is added and mixed to and with said powder. A ram 5 is thereafter lowered to pressurize the powder. The extrusion pressure is then increased and the initial pressure is loaded to the powder 4 as the powder 4 is compressed. The powder is simultaneously sintered when the pressure is balanced and while such pressure is maintained for certain time. The plate 3 and the powder 4 are immediately extruded upon completion of the sintering. The plate 3 is formed to the thickness at which the plate withstands the compressive force before the completion of the above-mentioned sintering and to the thickness enough for cladding approximately the entire extruded length of the powder 4 to a sleeve-shape. The sintered body bonded integrally with the sleeve shaped clad extruded layer 7 of the Al or Al alloy on the core part 8 is thereby obtd.