Simultaneously enhanced strength and ductility of 6xxx Al alloys via manipulating meso-scale and nano-scale structures guided with phase equilibrium

作     者：Qiang Lu Kai Li Haonan Chen Mingjun Yang Xinyue Lan Tong Yang Shuhong Liu Min Song Lingfei Cao Yong Du Qiang Lu;Kai Li;Haonan Chen;Mingjun Yang;Xinyue Lan;Tong Yang;Shuhong Liu;Min Song;Lingfei Cao;Yong Du

作者机构：State Key Laboratory of Powder MetallurgyCentral South UniversityChangsha 410083China Institute for Materials MicrostructureCentral South UniversityChangsha 410083China International Joint Laboratory for Light Alloys(Ministry of Education)College of Materials Science and EngineeringChongqing UniversityChongqing 400044China 

出 版 物：《Journal of Materials Science & Technology》 (材料科学技术（英文版）)

年 卷 期：2020年第41卷第6期

页      面：139-148页

核心收录：

学科分类：08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：financially supported by the National Natural Science Foundation of China(Nos.51531009,51711530713 and 51501230) the Central South University(No.2018gczd033) 

主　　题：Aluminum alloys Mg/Si atomic ratio Constituent Precipitates Three-dimensional atom probe(3DAP) 

摘      要：Excellent comprehensive mechanical properties including good formability,high strength and high ductility are prior demands for Al-Mg-Si-Cu *** study utilizes calculation of phase diagram(CALPHAD)to simplify the alloy design and meet these ***,CALPHAD was used to finely tune the Mg/Si atomic ratio in solid solution and accurately control the type and content of second phases,especially to avoid the formation of the harmful constituent phaseβ-Al Fe *** and dispersoids of only-Al Fe Mn Si phase were found in the alloy *** optimized microstructure with fine grains,micro scale constituents,densely distributed submicron scale dispersoids and extremely dense nano precipitates provides effective impediment to dislocation gliding and induces transgranular ***,the designed alloy has better comprehensive mechanical properties than other 6 xxx series aluminum alloys,including excellent formability,strength and *** low T4P strength of 149 MPa as well as the high elongation of 26.1%implies the alloy’s applicability to automobile body panel *** yield strength was rapidly improved from 149 MPa to 277 MPa during the paint bake ageing,because the number density of precipitates is twice as high as that of some other 6xxx ***,the elongation was kept at a high level of 20.0%.