AMORPHOUS IRON ALLOY WITH RESISTANCE TO PITTING CORROSION, CREVICE CORROSION, STRESS CORROSION CRACKING AND HYDROGEN EMBRITTLEMENT

摘要

PURPOSE:To obtain an amorphous Fe-Cr-P alloy with superior resistance to pitting corrosion, crevice corrosion, stress corrosion cracking and hydrogen embrittlement by specifying the amounts of Cr, C, B, C+B, P and C+B+P in an Fe-Cr-P alloy. CONSTITUTION:A molten alloy is sprayed on the inside of a drum rotating at a high speed in an inert atmosphere and cooled at a very high cooling rate to obtain an amorphous alloy. At this time, the alloy is composed of, by atom, 1- 40% Cr, =0.01% C, =0.01% B (C+B=2-35%), 0-33% P(C+B+P=7-35) and the balance Fe. In case of less than the lower limit of Cr, the resistance to pitting corrosion, crevice corrosion, stress corrosion cracking and hydrogen embrittlement is deteriorated, and in case of more than the upper limit of Cr, it is difficult to manufacture the amorphous alloy. C and B promote the formation of the amorphous structure, and P promotes the formation and enhances the corrosion resistance. Only when the amounts of C+B, P and C+B+P are within said ranges, the amorphous alloy can be manufactured.