Sheet specimens of copper and 70-30 brass, with stacking-fault free energies of 78 and 14mJ/m2, respectively, were variously annealed to produce a range of four different grain sizes and were then cold-rolled to reductions in thickness of 5, 10, 15, 45 and 60%. Plots of the 0.2% off-set yield stress, ultimate tensile stress and residual microhardness versus the reciprocal square root of the grain size showed that a Hall-Petch-type relationship could be applied in all cases.

Effect of Prestrain and Stacking-Fault Energy on the Application of the Hall-Petch Relation in FCC Metals and Alloys. S.L.Wang, L.E.Murr: Metallography, 1980, 13[3], 203-24