Corrosion Behavior of a Newly Developed 10Mn-7Cr-5Cu Alloy White Iron in Marine Atmosphere

摘要

Fe- 10Mn- 7Cr- 5Cu alloy white iron was heat treated to investigate the effect of microstructural changes on hardness and corrosion behavior in 5% NaCl solution. Microstructures consisting of martensite + austenite + massive carbides, martensite + austenite + massive carbides + dispersed phase particles, austenite + massive carbides + dispersed phase particles and austenite + massive carbides were observed. Microstructural features, hardness values and corrosion rates exhibited by the experimental alloy confirmed that the alloy can be successfully used as a corrosion resistant material. Microstructures comprised of mostly austenite were found to be better than those comprised of martensite + austenite from the point of view of corrosion resistance. Presence of needle shaped carbides and dispersed carbides while raised hardness favourably, adversely influenced corrosion resistance due to an unfavorable morphology and enhanced galvanic action.