Effect of intermediate thermomechanical treatment on microstructure and properties of 2A97 Al-Li alloy
YU Juan, LU Zheng, LU Yuan, XIONG Yan-cai, LI Guo-ai, FENG Zhao-hui, HAO Shi-jia
Beijing Engineering Research Center of Advanced Aluminum Alloys and Applications, AECC Beijing Institute of Aeronautical Materials, Beijing 100095, China
Abstract：Effect of intermediate thermomechanical treatment on tensile properties at short-transverse direction, intergranular corrosion, macrostructure and microstructure of 2A97 Al-Li alloy thin plate were studied by tensile testing,intergranular corrosion, EBSD and TEM.The results show that with the increase of compression deformation, the strength and elongation of the alloy increase first and then decrease slightly. When compression deformation is 20%, the grain size of recrystallization is fine and the uniformly dispersed δ' can be found in the grains,δ' phase located in the grain boundary is discontinuously distributed,the tensile property is the best,and the elongation rate is obviously improved;when the compression deformation is 25%, the intergranular corrosion resistance of the alloy is the best. The tensile and corrosion properties of the alloy are jointly affected by the interaction of grain morphology and precipitated phase.
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2021, Vol. 49 
