Effects of Precipitated Particles on Microstructure Evolution during Thermo-Mechanical Processing of Al-Zn-Mg-Cu Alloy

Abstract:

Two intermediate thermal mechanical treatment (ITMT) Processes were designed for investigation the influence of multi-scale precipitated particles on microstructure evolution during thermo-mechanical processing of Al-7.6Zn-1.5Mg-1.75Cu-0.12Zr alloy by hot compressive experiments and microstructure testing of OM and EBSD. It is found that the size and distribution of precipitated particles preprocessed by over-aging at 400°C for14h can meet the particle stimulated nucleation of recrystallization. Refined and uniform grains present in the sample after hot deformation at about 20 of LnZ up to 80% reduction and subsequent final solid solution treatment. But for samples preprocessed by solid solution at 435°C for 2h and aging at 200°C for 12h, Refined uniform recrystallized grains or recovery sub-grains in elongated grains present in the samples after hot deformation at about 25 of LnZ up to 60% reduction followed by annealing at 350°C for 0.5h and final solution treatment.

• Periodical: Materials Science Forum (Volume 879)
• Pages: 318-323
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.879.318
• Online since: November 2016
• Authors: Hui Qin Chen*, Kun Zhang, Xiao Dong Zhao
• Keywords: Al-Zn-Mg-Cu Alloys, Microstructure Evolution, Precipitated Particles, Thermo-Mechanical Processing

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