Microstructure and properties of 7B05 aluminum alloy after multi-stage aging treatment
7B05 aluminum alloy profile with excellent comprehensive properties was ob-tained after multi-stage aging treatment with an optimized new process,i.e.natural aging for 72 h+120 ℃/24 h+185 ℃/105 min+90 ℃/12 h+150 ℃/12 h.After treatment,the precipitation configuration in the alloy is dominated by ŋ'phase and supplemented by GP+ŋ phase,the grain boundary phase is discontinuously distributed,and the width of precipita-tion-free zone is controlled at about 100 nm.The tensile strength,yield strength and elonga-tion after fracture reach 373 MPa,324 MPa and 16.4%respectively,and the intergranular corrosion grade is 2.