PURPOSE:To sacrifice strength at high temp. and to improve toughness at lower temps. by compacting a powder mixture of TiAl and Al, sintering the resulting green compact, and then infiltrating a low melting point material into the resulting sintered compact. CONSTITUTION:Respective powders of TiAl and pure Al are mixed so that TiAl:Al=(50-95):(50-5), by weight percentage, is satisfied. The resulting powder mixture is compacted and sintered. Then, a molten material, such as phosphor bronze, having a melting point lower than that of the resulting sintered compact and also having ductility is brought into contact with this sintered compact and infiltrated into the porous body. At this time, infiltration temp. is regulated to about 1000-1150 deg.C and heating is exerted over about 0.5hr, by which phosphor bronze in the amount of about 10-50% based on the weight of the sintered compact is infiltrated. By this method, the TiAl grains which are brittle in the state of single phase are surrounded by phosphor bronze, and strength and toughness can be improved as a whole. Further, machinability and wear resistance can also be improved. As the low melting point material, aluminum bronze, bronze, Cu-Pb alloy, etc., can be used other than phpsphor bronze.
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