Texture and fatigue behavior of ultrafine grained copper produced by ECAP

Abstract

Electrolytic Tough Pitch (ETP) and Fire Refined High Conductivity (FRHC) copper samples were severely deformed by equal channel angular pressing (ECAP) and the effect of plastic deformation on the microstructure, texture and fatigue was investigated. The microstructural behavior was determined by analysis of the final texture through Inverse Pole Figures (IPF) and Orientation Distribution Function (ODF) maps, which revealed a marked decrease in the normal grain size of the ECAPed coppers and also the presence of recrystallization processes. The effect of the initial texture on the evolution of the texture after 8 ECAP passes for the two coppers was also analyzed. The results showed that the annealed materials presented a marked anisotropy, with a texture controlled by the 〈110〉 fiber. Additionally, the fatigue behavior of ultrafine grained coppers produced by ECAP was discussed briefly with respect to the macroscopic shear banding and fatigue lives. Experimental results also suggest that the fatigue behavior of ultrafine grained coppers processed by ECAP is quite different from conventional grained coppers, as the deformed materials presented a significant increase in the fatigue limit.