Improving intergranular corrosion resistance in a nickel-free and manganese-bearing high-nitrogen austenitic stainless steel through grain boundary character distribution optimization

Grain boundary character distribution (GBCD) and the effect of GBCD optimization on the intergranular corrosion (IGC) of a cold rolled and subsequently annealed nickel-free and manganese-bearing high-nitrogen austenitic stainless steel were investigated. The results show that the fraction of low Σ coincidence site lattice boundaries increases from 47.3% for the solid solution treated specimen to 83.3% for the specimen cold-rolled by 7% and then annealed at 1423 K for 10 min. Σ3 boundaries of high fraction effectively interrupt the connectivity of non-corrosion-resisting boundaries (special boundaries like Σ9, Σ27, etc. and general high angle boundaries) network, thus improving the IGC resistance.