中南大学学报（自然科学版）2026，Vol.57Issue(5)：2108-2121,14.DOI:10.11817/j.issn.1672-7207.2026.05.017
均匀化工艺对高速列车用Al-Mg-Si合金组织与力学性能的影响
Effect of homogenization process on microstructure and mechanical properties of Al-Mg-Si alloy for high-speed trains
摘要
Abstract
The effects of different homogenization processes on the microstructure and mechanical properties of high-strength Al-Mg-Si alloys for high-speed trains were investigated using scanning electron microscopy(SEM)and transmission electron microscopy(TEM).The results indicate that homogenization effectively eliminates dendritic segregation in the as-cast microstructure,improves compositional uniformity,and promotes dissolution of non-equilibrium phases at grain boundaries.One-step homogenization at 550℃/10 h reduces the area fraction of α-Al(FeMn)Si crystalline phases from 1.86%in the as-cast state to 0.93%.Compared with one-step homogenization,three-step homogenization at 300℃/4 h+420℃/6 h+550℃/8 h significantly promotes precipitation of nanoscale α-Al(FeMn)Si dispersoids,increasing their area fraction from 0.90%to 2.08%.However,homogenization reduces the number of particles stimulating recrystallization nucleation,and Al3Zr dispersoids fail to precipitate effectively,resulting in severe grain coarsening in the T6 state,the one-step homogenized sample exhibits the largest grain size of 307.0 μm.Furthermore,homogenization adversely affects the strength of the T6-treated alloy.The tensile strength of homogenized alloys decreases by 39.0-46.8 MPa compared with the non-homogenized specimen,which achieves 393.3 MPa and an elongation of 13.5%in the T6 temper,demonstrating a good strength-ductility balance.Ductility improves with increasing homogenization steps,and the elongation reaches 15.3%after three-step homogenization.关键词
Al-Mg-Si/高速列车/均匀化处理/α-Al(FeMn)Si相/组织与性能Key words
Al-Mg-Si/high-speed trains/homogenization/α-Al(FeMn)Si phase/microstructure and properties分类
矿业与冶金引用本文复制引用
袁忠禹,李俊,叶凌英,唐建国,刘胜胆..均匀化工艺对高速列车用Al-Mg-Si合金组织与力学性能的影响[J].中南大学学报（自然科学版）,2026,57(5):2108-2121,14.基金项目
国家重点研发计划项目(2023YFB3710401)(Project(2023YFB3710401)supported by the National Key R&D Program of China) （2023YFB3710401）
