Influence of precipitates on the grain refinement in CuFe2 alloy processed by rolling with cyclic movement of rolls

摘要

A CuFe2 alloy in solution treatment and in age hardenable states was processed by rolling with cyclic movement of rolls (RCMR) in order to investigate the influence of the precipitates on grain refinement. After applying two different aging treatments, various populations of second phase Fe particles were obtained: coherent with particle diameter and interparticle distance of about 10 nm and 40 nm, respectively, and not coherent with particle size and interparticle distance of about 100 nm and 200 nm, respectively. The resulting deformed structures were analyzed using light microscopy (LM), high resolution electron backscattered diffraction (EBSD) system coupled to a scanning electron microscope (SEM) and scanning transmission electron microscopy (STEM). Moreover, a microtensile test was performed on the deformed material. It was found that the presence of second phase particles has a significant effect on the formation of ultrafine grain (UFG) structure during the RCMR deformation. The presence of grains/subgrains with a high internal dislocation density and with non-equilibrium grain boundaries is the typical feature of the microstructure with a high- density of coherent Fe particles in the matrix. A closer inspection of the microstructure reveals the development of deformation twins and microshear bands. (C) 2016 Elsevier Ltd. All rights reserved.