Studies show that the proper solid solution treatment(SST)is a key step in the precipitation strengthening of AA7150 Al alloy.Despite the superior characteristics of the fully dissolved phase,it has major drawbacks,in...Studies show that the proper solid solution treatment(SST)is a key step in the precipitation strengthening of AA7150 Al alloy.Despite the superior characteristics of the fully dissolved phase,it has major drawbacks,including high consumption of energy and low efficiency.Recently,electropulsing treatment(EPT)has been proposed to study dissolved precipitations and modify microstructures of AA7150 Al alloy faster than conventional SST.Experiments have been conducted in the present article,and the obtained results show that EPT can promote the rapid dissolution of theη’phase at relatively low temperatures in only 20 s.Meanwhile,the strength and ductility of electropulsed samples decrease drastically.Compared with conventional SST,EPT accelerates recrystallization and obtains relatively fine grains after 20 and 50 s electric pulses.Moreover,as the EPT time increases,the corresponding non-uniform local heating and the electron force promote dislocation generation and annihilation.展开更多
基金financially supported by the Fundamental Research Funds for the National Key R&D Program of China(No.2017YFB0306300)the Hunan Provincial Innovation Foundation for Postgraduate(No.CX20200185)+1 种基金the Fundamental Research Funds for the Central Universities of Central South University(No.2020zzts098)the National Natural Science Foundation of China(Nos.19055551,51675538 and 51601060)。
文摘Studies show that the proper solid solution treatment(SST)is a key step in the precipitation strengthening of AA7150 Al alloy.Despite the superior characteristics of the fully dissolved phase,it has major drawbacks,including high consumption of energy and low efficiency.Recently,electropulsing treatment(EPT)has been proposed to study dissolved precipitations and modify microstructures of AA7150 Al alloy faster than conventional SST.Experiments have been conducted in the present article,and the obtained results show that EPT can promote the rapid dissolution of theη’phase at relatively low temperatures in only 20 s.Meanwhile,the strength and ductility of electropulsed samples decrease drastically.Compared with conventional SST,EPT accelerates recrystallization and obtains relatively fine grains after 20 and 50 s electric pulses.Moreover,as the EPT time increases,the corresponding non-uniform local heating and the electron force promote dislocation generation and annihilation.
