A grain boundary engineering approach was made to improve the microstructure of a commercial Pb-base alloy. For the purpose of enhancing the resistance against intergranular corrosion, cracking and creep, a thermomechanical processing route was sought to promote special boundaries, specifically coincidence site lattice boundaries. Through a combination of cold working and recrystallization heat treatment, it was possible to increase the fraction of low-Σ coincidence site lattice boundaries more than 91%. Annealing twins, produced during the thermomechanical processing, were identified as a key factor for regeneration of coincidence site lattice boundaries. Multiplication of the coincidence site lattice boundaries was interpreted in terms of the so-called Σ3 regeneration model.

A Grain Boundary Engineering Approach to Promote Special Boundaries in Pb-Base Alloy. D.S.Lee, H.S.Ryoo, S.K.Hwang: Materials Science and Engineering A, 2003, 354[1-2], 106-11