Effects of Nano-Grains and Deformation Nano-Twins on Electrochemical Corrosion Behavior of DZ125 Nickel-Based Superalloy

Nano-grains on the surface region of the DZ125 directionally solidified nickel based superalloy is obtained through burnishing processing at both room and low temperature. Compared to the low temperature burnished (LTB) specimen, the {111}/[112] type nano-twins are generated on the room temperature burnished specimen (specimen RTB). The results demonstrate that the nano-grains could improve the corrosion resistance and promote the formation of compact corrosion product films on the burnished DZ125 alloy surface in a 3.5 wt% NaCl solution. The combined effects of local deformation nano-twins and lower percentage of Cr₂O₃ in corrosion product film lead to the fact that the specimen RTB exhibits a relatively lower corrosion resistance compared to the specimen LTB.