METHOD FOR PRODUCING Fe-50Cr ALLOY USING PLASMA DISCHARGE SINTERING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a method for producing Fe-50Cr as ferritic stainless steel.;SOLUTION: Fe and Cr powders are subjected to a dissolution process to forge an Fe-50Cr alloy. This alloy is subjected to an Ar gas atomizing process to obtain the powder of the alloy of about 75 to 100 μm. This powder is sintered by using a discharge plasma sintering apparatus under the conditions where compacting pressurizing force is 50 to 70 MPa, sintering temperature is 800 to 1,100°C, sintering time is 20 to 90 min, and the sintering atmosphere is held to a vacuum state of about 10^-3. After that, the alloy is cooled at least to about 500°C. Next, the vacuum state is broken, and air is flowed therein, and rapid cooling is performed. Finally, when the temperature is lowered to 250 to 200°C, the alloy is discharged from the furnace, and the crystal grain size of the base material of the alloy is refined.;COPYRIGHT: (C)2003,JPO