By twin-induced grain boundary engineering utilizing optimized one-step thermomechanical processing with 3% pre-strain and subsequent annealing (1240K, 72h), a very high frequency of coincidence site lattice boundaries (86%) was introduced into type-316 austenitic stainless steel. The resulting steel showed a remarkably high resistance to intergranular corrosion during ferric sulfate–sulfuric acid tests. A coincidence site lattice frequency of over 82% could result in a very low percolation probability of random boundary networks in per-threshold and a remarkable suppression of intergranular deterioration during twin-induced grain boundary engineering of austenitic stainless steels.

Twin-Induced Grain Boundary Engineering for 316 Austenitic Stainless Steel. M.Michiuchi, H.Kokawa, Z.J.Wang, Y.S.Sato, K.Sakai: Acta Materialia, 2006, 54[19], 5179-84