Softening and Strengthening Mechanism Induced by Cold Work in a Cu-Al₂O₃ Composite with 0.1 wt.% Al Content

The softening and strengthening mechanism induced by cold work of Cu-Al₂O₃ composite with 0.1wt.% Al content was investigated in this paper. These results show the microstructure while cold work exhibits a strong <001>//X0 and <111>//X0 double fiber texture along the deformation direction (X0). However, except for grain refinement, the intensity of the <111>//X0 fiber texture gets better as the plastic deformation increased levels, accompanying the formation of high-density dislocations. As a result, the improving strengthening effects from the grain boundary, texture, and dislocation are responsible for hardening induced by the cold work. However, the dislocation strengthening effect induced by the cold work with large plastic deformation is lower than that with moderate plastic deformation, resulting from the decreasing dislocation density. Therefore, it is suggested that the work softening phenomenon by the large plastic deformation is attributed to the weakening dislocation strengthening compared to the moderate plastic deformation.