Evolution of nanostructure in α-brass upon cryorolling

The microstructure of α-brass has been investigated at 98% and 200% of cryorolling (CR). Severe cryorolling introduces microscopic shear bands, forms primary and secondary twins, and the twin density increases with increase of plastic strain. Even though the average hardness values in CR200 (197 Hv) does not increase significantly than that of CR98 (189 Hv), but the hardness distribution become narrow in CR200 due to the narrow size distribution and refinement of twin lamellar spacing. The microscopic mechanism on the evolution of homogeneous nanostructure in α-brass has been reported.