摘要
汽车构件轻量化是实现节能减排的重要途径,而关键部件在满足比强度的同时还需具备较好的使役性能。铝合金材料因其轻质、高强、易加工等诸多优势,常被用于汽车转向节、控制臂、轮毂等关键零件的加工制造。以转向节零件为例,由于其结构较为复杂,采用传统加工工艺难以满足制造精度与使役强度的双重需求,而采用增材制造可有效解决这一难题。采用选区激光熔化工艺对A357铝合金进行了制备成形,并针对其微观组织、力学性能及疲劳破坏机制进行研究。结果表明,增材制造A357铝合金为等轴晶与柱状晶交替分布存在的双态组织;合金抗拉强度可达337~351 MPa,断后延伸率为10.3%~11.0%;随着疲劳载荷在不断降低,循环加载次数逐渐增加,在100 MPa应力状态下,循环加载次数可达3.08×10^(6)次。
Reducing the weight of automobile components is of significant importance in achieving energy efficiency and emission reduc-tion.To meet the performance requirements and specific strength necessary for their intended use,key components must possess supe-rior service performance.Due to the advantages of light weight,high strength and easy processing,aluminum alloy is always used in the processing and manufacturing of automobile parts,such as steering knuckle,control arm,wheel hub,etc.Taking the steering knuckle part as an example,due to its complex structure,it is difficult to meet the dual requirements of manufac-turing accuracy and service strength by using traditional processing technology,but additive manufacturing can solve this prob-lem effectively.In this paper,the A357 aluminum alloy was prepared by selective laser melting,and its microstructure,me-chanical properties and fatigue failure mechanism were studied in detail.The results show that the microstructure of A357 alu-minum alloy is equiaxed and columnar grains with an alternate distribution.The tensile strength of the alloy is 337-351 MPa,and the elongation after fracture is 10.3%-11.0%.As the fatigue load decreases,the number of cyclic load applications gradually in-creases.Under the stress state of 100 MPa,the number of cyclic load applications can reach as high as 3.08×10^(6)times.
作者
王文超
Wang Wenchao(School of Mechanical and Electrical Engineering,Zhengzhou Railway Vocation&Technical College,Zhengzhou 451460,Henan,China)
出处
《应用激光》
CSCD
北大核心
2023年第11期26-32,共7页
Applied Laser
基金
2023年郑州铁路职业技术学院科研基金项目(2023KY001)。
关键词
增材制造
选区激光熔化
A357铝合金
微观组织
力学性能
sadditive manufacturing
selective laser melting
A357 aluminum alloy
microstructure
mechanical properties
