Two-stage Hall-Petch relationship in Cu with recrystallized structure

Y.Z. Tian^a^,^*(

), Y.P. Ren^b, S. Gao^c^,^d, R.X. Zheng^e, J.H. Wang^f, H.C. Pan^a, Z.F. Zhang^g^,^h, N.T suji^c^,^d, G.W. Qin^b

Fig. 4.. (a) Plot of Hall-Petch slope against (Gb)^1/2 for Cu, Al [7], Ni60Co40 alloy [20], CoCrNi alloy [20] and IF steel [21,22] and (b) Plot of critical grain size d_c against γ /(Gb) for Cu, Al [7], Ni60Co40 alloy [20] and CoCrNi alloy [20]. d_c is related to the transition from stage I to II Hall-Petch relationship.