Corrosion behavior of high-purity Fe-Cr-Ni alloys in the transpassive condition

Journal Article · Sat Jan 01 04:00:00 EST 2000 · Corrosion (Houston)

DOI:https://doi.org/10.5006/1.3280524· OSTI ID:20014473

Mayuzumi, M; Ohta, J; Kako, K

The corrosion behavior of high-purity (99.99%) Fe-Cr-Ni alloys was investigated in 13 kmol/m{sup 3} [0.36 kmol/ft{sup 3}] nitric acid (HNO{sup 3}) with and without ceric (Ce{sup 4+}) ions to clarify the effect of purity on the transpassive corrosion of stainless steel. Almost no intergranular corrosion was observed in the high-purity alloys, although the corrosion rate of the matrix region was almost the same as that of a commercial stainless steel with the same Cr and Ni contents. Because of the improved intergranular corrosion resistance of the high-purity alloys, the beneficial effect of the purification became significant in the corrosion condition where the grain separation became pronounced in the commercially pure alloys. A purity of 99.99% was good enough to use the solution-annealed Fe-Cr-Ni alloys as the base materials to examine the effect of impurities and/or alloying elements on transpassive corrosion. However, further purification will be necessary to use in the aged condition since intergranular corrosion was observed in aged high-purity alloys.

• Research Organization: Central Research Inst. of Electric Power Industry, Tokyo (JP)
• OSTI ID: 20014473
• Journal Information: Corrosion (Houston), Journal Name: Corrosion (Houston) Journal Issue: 1 Vol. 56; ISSN 0010-9312; ISSN CORRAK
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CERIUM
CHROMIUM-NICKEL STEELS
CORROSIVE EFFECTS
INTERGRANULAR CORROSION
METALLURGICAL EFFECTS
NITRIC ACID