Effect of Parking Time on the Microstructure and Properties of 7050 Aluminum Alloy

Abstract

The duration of the parking time between quenching and artificial aging can affect the final mechanical and corrosion properties of the material after artificial aging, etc. At present, there are fewer studies on the parking time before artificial aging, and this paper investigates the influence of the parking time before artificial aging on the microstructure and properties of 7050 aluminum alloy. The results show that: with the prolongation of the parking time, the proportion of HAGBs of the alloy is gradually increased through EBSD analysis, the dislocations are mainly concentrated in HAGBs and areas with dense GBs, the precipitated phase of the alloy continuously precipitates and grows at the GBs, the alloy’s hardness shows a trend of stabilization and then decreasing, and the corrosion resistance is stabilized and then deteriorated quickly with the prolongation of the parking time. The alloy has stabilized comprehensive performance when the storage time does not exceed 6 h, with microhardness of 132.2 HV, the Ecorr of −0.991 V and −1.007 V, the Icorr of 6.14×10−8 A·cm−2 and 4.16×10−7 A·cm−2.