High temperature deformation of aluminium bronze

Abstract

Hot compression tests were carried out on commercial Cu–8 wt-%Al alloy to test the effect of the deformation conditions on high temperature deformation characteristics and the final structure of the hot deformed material. Dynamic recrystallisation of the material was found to operate at deformation temperatures above ∼900 K. Nucleation and growth of recrystallised grains were observed for specimens deformed at temperatures below ∼1000 K. However, the flow stress peaks that usually mark the onset of dynamic recrystallisation were hardly seen on the stress–strain curves. During hot deformation of Cu–8 wt-%Al alloy above ∼1000 K the interaction of →β phase transformation and deformation processes affected both the flow stress value and the structure of the material. In particular, post-deformation water quenching of the specimens resulted in martensitic transformation within pre-existing β grains. Moreover, local coherent iron particles were detected within β and neighbouring grains.