The texture evolution of cold drawing copper wires produced by continuous casting was measured by X-ray diffractometry and electron back-scatter diffractometry,and was simulated using Taylor model.The results show that in the drawn poly-crystal copper wires produced by traditional continuous casting,111 and 100 duplex fiber texture forms,and with increasing strain,the intensities of 111 and 100 increase.In the drawn single-crystal copper wires produced by Ohno continuous casting,100 rotates to 111,and there is inhomogeneous distribution of fiber texture along radial direction of the wires,which is caused by the distribution of shear deformation.Compared with 100,111 fiber texture is more stable in the drawn copper wires.Comparison of the experimental results with the simulated results shows that the simulation by Taylor model can analyze the texture evolution of drawn copper wires.
By using transmission electron microscopy, the microstructures of drawn industrial single crystal copper wires produced by Ohno Continuous Casting(OCC) process were analyzed. The results show that the typical microstructures in the wires mainly include extended planar dislocation boundaries, a small fraction of twins and some dislocation cells sharing boundaries parallel to drawn direction. Besides the typical microstructures, 9R structure configurations were observed in the wires. The formation of 9R polytypes may be caused by the coupled emission of Shockley dislocations from a boundary.
By means of electron backscattering diffraction and transmission electron microscopy the microstructure and texture of drawn single crystal copper with initial orientation (110) parallel to axial direction have been investigated in the present work. In or- der to analyze the effect of initial orientation on microstructure and texture of drawn copper, the results of the drawn (110) sin- gle crystal copper wires have been compared with (100) and (111) single crystal copper wires. It is found that the grain subdi- vision of (110) single crystal is more evident than that of (100) and (111), and the textures consisting of (111) and (100) abruptly form in the drawn (110) single crystal. At high strains, due to shear strain, the distribution of fiber textures is imho- mogenous along the radial direction of drawn (110) single crystal copper wires. (100) is near the surface and (111) is at the center. The microstructure results of drawn (110) single crystal show that at low strains, it can be characterized as two kinds of geometrically necessary boundaries with noncrystalline character. At medium strains, S bands can be observed. At high strains, lamellar boundaries form. Mean misofientation and average spacing of dislocation boundary are larger in drawn (110) single crystal, as compared with (111) and (100). In drawn (110) single crystal with high strains, the bimodal distribution forms at lower strains than in drawn (100) single crystal, which is because the dislocation boundaries with high angle are contributed by not only the boundary between (111) and (100) fiber textures but also the boundary in (111) or (100) texture.