Abstract:The near-solvus pre-precipitation following higher temperature solution treatment was performed on 7055 aluminum alloy. The effect of the pre-precipitation on the microstructure, age hardening and stress corrosion cracking of 7055 alloy was investigated. The optical and transmission electron microscopy results show that the near-solvus pre-precipitation can be limited to grain boundary and enhance the discontinuity of grain boundary precipitates in the sequent age. The stress corrosion cracking resistance of aged 7055 alloys could be improved with non-deteriorated strength and plasticity via the pre-precipitation.

Key words:  7055 aluminum alloy; stress corrosion; precipitation; solution