During last decades, many attempts has been done for the development of sever plastic deformation (SPD) process for producing ultra fine grained metals. In these techniques, severe plastic strains can be applied to solid bulk materials without any significant changes in the specimen’s overall dimensions. Among different SDP techniques, ECAP has attracted most attention, because it is effective in the production of UFG structures. In this research, after 2 passes ECAP process and annealing at 520 o C for 2 hr, ECAP process up to 10 passes was carried out on as-cast 8090 Al-Li alloy specimens with different route A and Bc in the ECAP die with ? = 120 o at 250 o C. Then, for investigating the effect of precipitation hardening after the ECAP process, 2, 4, 6 and 8 passes ECAPed samples was precipitate hardened. Microstructures of different samples were studied with EBSD equipment. Tensile and hardness test were performed for evaluating the mechanical properties of ECAP samples before and after precipitation hardening. In order to clarify the failure mode, fracture surfaces after tensile test were observed by Scanning Electron Microscopy (SEM). Moreover, X-ray diffraction system equipped by goniometer was utilized to investigate the variation of texture of the samples. The results showed that significant grain refinement was obtained by ECAP process and the grain size decreased from ~ 30 micron in annealed sample to below 1 micron (ultra-fine range) after 6 passes ECAP with route A. It is observed that at first stages of ECAP process, the hardness and tensile strength were increased and decreased by subsequent passes. Precipitate hardening of samples after ECAP processing results in significant increase in hardness and tensile strength, but elongation of the sample strongly increased as after 2 passes ECAP and precipitate hardening, the hardness of the sample was almost two times higher than the annealed sample. Different routes and precipitate hardening result in different texture in samples. The important point was brass texture (}110 {112 ) that was obtained after precipitate hardening. Key words: ECAP, 8090 Al-Li, tensile strength, elongation, texture, ultra fine grain structure
