A study was made of the relationship between iterative multi-stage thermomechanical treatments, grain boundary crystallography and resultant ductility in α-brass. The grain boundary crystallographies were analyzed in terms of the proportions of coincidence site lattice types and also with regard to their proximity to the exact coincidence site lattice reference structure. The only coincidence site lattices which were present in significant proportions were Σ = 3, and those Σ = 3 lattices with an intermediate proximity with respect to the exact coincidence site lattice misorientation were identified as being high-mobility boundaries. The variation in the mobility at a Σ = 3 interface, as a function of the deviation from the exact coincidence site lattice configuration, was considered in detail. In the case of 2 selected specimens, modification of the strain-annealing regimes resulted in ductilities of 53 and 74%. The enhanced ductility of one of these specimens was attributed to a combination of strain-induced grain growth and increased proportions of Σ = 3 interfaces having an intermediate proximity to the exact coincidence site lattice misorientation.

The Effect of Low Strain and Annealing Iterations on the Ductility of α-Brass. H.Davies, V.Randle: Philosophical Magazine A, 2001, 81[11], 2553-64