Abstract:The microstructure evolution and properties of continuous columnar-grained (CCG) polycrystalline copper during intense drawing deformation at room temperature were investigated by optical microscope, scanning electron microscope, Vickers microhardness tester, and universal tensile testing machine. The stored energy was calculated according to the structural parameters of dislocation cells in different textures based on high-resolution electron backscattered diffraction. Results show that CCG microstructure is gradually thinned into fibrous tissue. The as-cast CCG polycrystalline copper has tensile strength of 168 MPa, elongation of 52%, and conductivity of 103%IACS. After the drawing deformation of 99% at room temperature, the tensile strength of CCG polycrystalline copper increases to 455 MPa. However, the elongation reduces to 3%, and the conductivity decreases 96.8%IACS. Both the transverse and longitudinal sections of CCG polycrystalline copper have <001> original preferred orientation. A large number of fiber textures of <111> orientation and a small number of fiber textures of <001> orientation are formed with increasing the drawing deformation amount. Cube texture of the transverse section gradually decreases, and S texture and Copper texture gradually increase. Meanwhile, the Cube texture and Goss texture of longitudinal section are gradually transformed into Brass texture, Copper texture, and S texture. The kernel average misorientation (KAM) value at grain boundaries and in the deformation bands is large. Additionally, with increasing the deformation amount, KAM value is gradually increased and the stress is more concentrated. Under the same deformation conditions, the transverse section has higher stored energy than the longitudinal section does, and <001> orientation fiber texture has lower stored energy than <111> orientation fiber texture does. After the strong plastic deformation, CCG polycrystalline copper still has a large number of deformation textures with “soft” <001> orientation, which is an important reason for its low work hardening rate and excellent cold deformation ability.