Effect of interstitial carbon and nitrogen on corrosion of FeCoCrNi multi-principal element alloys made by selective laser melting

The corrosion behaviors of selective laser melted (SLMed) FeCoCrNi multi-principal element alloys (MPEAs) with carbon or nitrogen addition in 0.5 M H2SO4 solution were investigated. Both C and N ad-dition refined the grains and introduced a heterogeneous structure in SLMed FeCoCrNi MPEA, but they had opposite effects on the corrosion behavior. The doped carbon participated as nano-sized carbides in SLMed MPEA, and localized galvanic corrosion occurred, degrading the corrosion resistance. The doped nitrogen was gathered with chromium and formed CrN chemical clusters in SLMed MPEA, and a protec-tive passive film with a higher Cr2O3/Cr(OH)3 ratio formed, which improved corrosion resistance.(c) 2023 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Automated summary

The corrosion behaviors of selective laser melted FeCoCrNi multi-principal element alloys with carbon or nitrogen addition in 0.5 M H2SO4 solution were investigated. Carbon and nitrogen additions refined the grains and introduced a heterogeneous structure, but had opposite effects on corrosion behavior. Doped carbon participated as nano-sized carbides and caused localized galvanic corrosion, while doped nitrogen formed CrN chemical clusters and resulted in a protective passive film with higher Cr2O3/Cr(OH)3 ratio.