Effect of electropulsing treatment on corrosion behavior of
nickel base corrosion-resistant alloy
nickel base corrosion-resistant alloy
(1. Key Lab for Anisotropy and Texture of Materials, Northeastern University, Shenyang 110819, China;
2. Department of High-temperature Materials, Central Iron and Steel Research Institute, Beijing 100081, China)
2. Department of High-temperature Materials, Central Iron and Steel Research Institute, Beijing 100081, China)
Abstract: Electropulsing treatment (EPT) was performed on a nickel base corrosion resistant alloy during aging. The effect of EPT on the microstructure and corrosion resistance of the alloy and the mechanisms were investigated. The results show that the intergranular corrosion resistance can be improved substantially without the degradation of mechanical properties of the alloy by EPT. The EPT has an effect of enhancing the interface diffusion rate of the alloying element, which is higher than the body diffusion rate. And thus discontinuous precipitation of M23C6 type carbides appears at the grain boundary in the alloy by EPT, which decreases the depletion extent of the alloying elements at the grain boundary substantially. As a result, the intergranular corrosion resistance of the alloy can be improved by the EPT without any degradation of mechanical properties.
Key words: nickel base alloy; electropulsing; discontinuous precipitation; intergranular corrosion