Effect of heat treatment on microstructures and mechanical properties of a bulk nanostructured Al-Zn-Mg-Cu alloy

Han-bin Chen1,2) and Bin Yang1) 1) State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China 2) No.59 Institute of China Ordnance Industry, Chongqing 400039, China

摘 要：A bulk nanostructured Al-10.0Zn-2.8Mg-1.8Cu alloy was synthesized by cryomilling first and then by spark plasma sintering （SPS）, and the effect of heat treatment on the microstructures and mechanical properties of this alloy were studied. Most MgZn2 particles with a coarse size lie on the grain boundaries of the SPS-processed sample. After solid solution and artificial aging, fine spherical-like MgZn2 particles precipitate uniformly in the grain interiors. No obvious grain growth is found after the heat treatment. A nanoindentation study indicates that no clear change is found in the Yong’s modulus of the nanostructured alloy after the heat treatment. However, the hardness of the nanostructured alloy increases by about 33% after the heat treatment, which is attributed to the effect of precipitation-hardening.

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