Effects of Thermo-Mechanical Treatment on the Microstructure of AA7085 Aluminum Alloy

Abstract:

The microstructure of pre-aged AA7085 rolled plate was studied by means of hardness tests, optical microscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction and electrical conductivity tests. The results show that supper refined and homogeneous precipitates were formed during pre-aging, but the hardness of the alloy was still relatively low. There occurred a large number of dislocations when the warm deformation was introduced, and the size of the intragranular precipitates firstly increases and then decreases and then increases with the dislocation density increasing, which was caused by the role of dislocations on inhibiting the formation of GP zone and promoting the nucleation and transformation of η phase. Meanwhile, the distribution of grain boundary precipitates also changed from continuous chain to coarsening interrupted distribution and the precipitate free zone (PFZ) broadened obviously.

• Periodical: Materials Science Forum (Volumes 794-796)
• Pages: 1193-1198
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.794-796.1193
• Online since: June 2014
• Authors: Hong Wei Tong, Wen Yi Liu*, Guang Jie Huang, Qing Liu
• Keywords: AA7085, Electrical Conductivity, Precipitate Free Zone, Thermo-Mechanical Treatment

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