Effect of intermediate annealing on microstructure and properties of 6016 aluminum alloy

doi:10.13251/j.issn.0254-6051.2021.08.032

Abstract

Abstract: Microstructure evolution in production process and effect of intermediate annealing on comprehensive performance of the 6016 aluminum alloy for automobile body sheet were studied by using scanning electron microscope and transmission electron microscope. The results show that continuous annealing has stronger grain refinement effect than furnace annealing. The reduction amount of cold rolling before intermediate annealing has a remarkable effect on fragmentization of the crystalline phases, decreasing the size from 4.38 μm to ~3.2 μm, i.e., reduced by ~27%, and the intermediate annealing treatment can weaken uneven yield elongation of the T4P automobile body sheet. Whereas the slow heating rate of furnace annealing and long holding time at medium temperature lead to grain boundary precipitation and coarsening of Mg₂Si.

Key words: 6016 aluminum alloy, automobile body sheet, furnace annealing, continuous annealing, Mg₂Si

CLC Number:

TG156.2

Ding Xuan, Gan Yurong, Zhang Chunju, Wang Liqiang, Yang Mingqiu, Li Hui. Effect of intermediate annealing on microstructure and properties of 6016 aluminum alloy[J]. Heat Treatment of Metals, 2021, 46(8): 174-179.

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