The partition coefficient of alloying elements and its influence on the pitting corrosion resistance of 15Cr-2Ni duplex stainless steel

[Display omitted] •The partition coefficient is more uniform with the increased δ volume fraction.•Pitting corrosion resistance of δ and γ phases varies with the partition coefficient.•Developing single-phase porous stainless steel by corrosion etching is suggested. This work investigates the influence of heat treatment parameters including annealing temperature, time and cooling rate on the partition coefficient of alloying elements between ferrite and austenite phases, and obtains the pitting corrosion resistance comparison between ferrite and austenite phases. The partition coefficient varies with the annealing temperature, time and cooling rate, which is associated with the change of ferrite volume fraction. When ferrite volume fraction increases, the partition coefficient becomes more uniform and close to 1. The contrast of pitting corrosion resistance between ferrite and austenite phases varies with the change of the partition coefficient of alloying elements.