PURPOSE: To make it possible to sinter in the air without deteriorating the quality, by evaporating the metal having a larger affinity for exygen than the metal of the molded product on the surface of the molded product with the laser at the preparation of the sintered product.
CONSTITUTION: By pressurizing and molding the powder of Fe, Cu, Ni, stainless steel, etc., the molded product for the sintered product is prepared. The metal having a larger affinity for oxygen than the metal constituting the molded product, such as Ti, Si, Al, Mg, etc., is evaporated on the surface of the above molded product by using the laser in a vacuum of about 10-3 Torr. This molded product is sintered by being heated for 30 minutes at 1100°C in the air. At this time, only the evaporated metal on the surface of the molded product is oxidized and the metal constituting the molded product is not oxidized, so that the sintered product of good quality is obtained. With this method, it is not required to use the reducing atmosphere as the atmosphere in the sintering furnace at the sintering, so that the sintering can be performed simply
MATSUMOTO SHIYUUJI
SHIBATA MITSUGI
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