Influence of stress state on plastic flow and ductile fracture of three 6000-series aluminium alloys

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:783

Article

Thomesen, Susanne¹  Hopperstad, Odd Sture^1,2  Myhr, Ole Runar^1,3  Borvik, Tore^1,2 

[1] Norwegian Univ Sci & Technol NTNU, Dept Struct Engn, Struct Impact Lab SIMLab, NO-7491 Trondheim, Norway

[2] NTNU, Ctr Adv Struct Anal CASA, NO-7491 Trondheim, Norway

[3] Hydro Aluminium Res & Technol Dev, NO-6601 Sunndalsora, Norway

关键词: Aluminium alloys;    Tension test;    Triaxiality;    Fractography;   

DOI  :  10.1016/j.msea.2020.139295

来源: Elsevier

【 摘 要 】

In this study, the plastic flow and ductile fracture of three 6000-series aluminium alloys commonly used for crash components in the automotive industry are characterised experimentally and the observations are related to microstructural features. The three alloys are used in the cast and homogenised condition after artificial ageing to temper T6 to ensure isotropic behaviour. Tension tests on smooth and notched axisymmetric specimens are carried out to reveal the stress-strain behaviour, ductility and fracture mechanisms of the materials for different stress states. Through the use of optical and scanning electron microscopes, the initial microstructure of the alloys and the fracture surfaces of the tension test specimens are investigated. The work-hardening of the alloys is analysed up to large strains. Whereas the ductility of two of the alloys falls into the trend of previous experimental data on 6000-series aluminium alloys, where the strain to failure decreases linearly with increasing yield stress, the third alloy stands out by combining high strength with high ductility. The excellent properties of the latter alloy are assumed to be due to a favourable size distribution of constituent particles.

【 授权许可】

Free