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The effects of sole Cr, Mn, Zr, Ti addition on the precipitation of secondary phases (especially AlCuYb), matrix recrystallization behaviour and tensile intergranular fracture of an AlZnMgCuYb based alloy has been investigated by using tensile test, together with detailed microstructural characterization XRD, TEM, SEM, and EBSD technique. The results indicate that coarse micro-scaled AlCuYb phase precipitated can not be inevitable in the Yb and Cu containing Al alloy. It is interesting that the least coarsen phases are formed in the AlZnMgCuYb-Mn alloy due to the precipitation of submicro-scaled Al₂₀Cu₂Mn₃ phase resulting in the effective decreasing of coarse AlCuYb phases. The addition of Zr to AlZnMgCuYb alloy can effectively inhibit the recrystallization of ɑ(Al) matrix by the formation of nano-scale coherent Al₃(Yb, Zr) dispersoids. However, the formation of AlCuYb phases consuming Yb will reduce secondary coherent Al₃(Yb, Zr) precipitation and particleSstimulated partial recrystallization nucleation, resulting in a decline in strength of AlZnMgCuYb-Zr alloy. T6-tempered AlZnMgCuYb-Zr and AlZnMgCuYb-Mn alloys still remain an unrecrystallized fiber-like structure, the fraction of low-angle grain boundaries (LAGBs) increased up to 50%, and the average grain size decreased to 2~7 μm. However, more homogeneous recrystallization grains are observed in Cr or Ti containing AlZnMgCuYb alloy, the fraction of high-angle grain boundaries (HAGBs) and the average grain size achieve 80% and 40-96 μm, respectively. The primary 1~3 μm Al₂CuMg particles, not coarse AlCuYb preferentially cracked, and cracking propagated along high-angle recrystallized grain boundaries or original grain boundaries with continuous, coarser grain boundary precipitates and broadening precipitate-freeSzones (PFZs) at its periphery.