Impact of Texture and Microstructure on In-plane Anisotropy of Ultra-high Strength Aluminium Alloy

  In order to master the impact of texture and microstructure on the in-plane anisotropy of tensile mechanical properties of ultra-high strength Al-Zn-Mg-Cu alloy,the extruded plate and its isothermal forged piece were manufactured. The microstructure, tensile mechanical properties and the intensity of texture were tested and the Schmidt factors were calculated. The relationship of the texture, microstructure and the tensile strength anisotropy were observed by means of single crystal model with Schmidt factor and Hall-Petch law. The results show that the alloy is dominated by deformation texture after intense deformation, and deformation textures leads lower strength of 45° and causes anisotropies. Fibrous tissue formed by extrusion is the main reason of the anisotropy in L and LT directions. The increased strength caused by {110} <112>Brass texture can counterbalance the anisotropy in L and LT directions caused by fibrous tissue. The chainlike distribution of the second phase particles in grain boundary is the key factor of lower elongation of LT and the elongation anisotropy, also it is relevant to the grain strength changes caused by textures.