**2.1 Preferred orientation and texture**

In some samples, the preferred orientation of planes creates by several mechanical processes such as accumulative roll bonding (ARB), cyclic extrusion compression (CEC) and equal channel angular pressing (ECAP) processes, etc. TEM image and SAED pattern of nanostructured Al 2024 alloy under ECAP process were demonstrated in **Figure 1(a)** and **(b)**, respectively. The SAED pattern of preferred orientation and textured nanostructured materials was formed from many partial rings or incomplete rings. Diffraction pattern of such materials can be described as an intermediate sample between a single and polycrystalline material. The texture produced in materials can be studied by the interpretation of their SAED. The preferred orientation {110} [001] was formed in Al 2024 alloy by this process [3].
