Microstructure and mechanical properties of ultra fine grained Cu-Zn and Cu-Al alloys produced by cryorolling and annealing

In the present paper, we present the microstructure and mechanical properties of cryorolled and annealed Cu-5 wt.% Zn and Cu-5 wt.% Al alloys. Ultrafine grained microstructures with very fine annealing twins are obtained after cryrolling and annealing at 250 °C for 15 min. The study of Young's modulus (E) variation with temperature revealed that E is lower (about ∼15%) in the as-rolled condition and it increases to the isotropic value after recrystallisation. This variation is attributed to the crystallographic texture that develops during rolling and recrystallisation. The Cu-Al alloy exhibited much higher strength (600 MPa) with similar strain to fracture (0.26) in comparison to Cu-Zn alloy (355 MPa). The higher strength of Cu-Al alloy is explained in terms of the higher contribution to solid solution strengthening of Al.