Dynamic deformation response of Al-Mg and Al-Mg/B4C composite at elevated temperatures

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

卷:712

Article

Rezayat, M.^1,2,3  Parsa, M. H.^3,4  Mirzadeh, H.³  Cabrera, J. M.² 

[1] Sahand Univ Technol, Dept Mat Engn, POB 51335-1996, Tabriz, Iran

[2] Univ Politecn Cataluna, Dept Ciencia Mat & Ingn Metalurg, EEBE, C Eduard Maristany 10-14, Barcelona 08019, Spain

[3] Univ Tehran, Sch Met & Mat Engn, Coll Engn, POB 11155-4563, Tehran, Iran

[4] Univ Tehran, Ctr Excellence High Performance Mat, Sch Met & Mat Engn, Tehran, Iran

关键词: High temperature dynamic deformation;    Constitutive analysis;    Microstructural investigation;    Flow stress behavior;   

DOI  :  10.1016/j.msea.2017.12.013

来源: Elsevier

【 摘 要 】

The dynamic deformations at high temperatures of Al-3 wt%Mg alloy and Al-3 wt%Mg/B4C composites with different volume fractions and particle sizes were studied using a dilatometer deformation instrument and a split Hopkinson pressure bar operating at strain rates of 10-1000 1/s. A comprehensive analytical procedure was developed to correct the effects of adiabatic heating, friction at interface of the specimen and bars, and strain rate variation, on flow stress curves. Then based on corrected data, a physical based constitutive equation was developed for modeling and prediction of flow stress. It was observed that composites in comparison with single phase alloy, after initial straining, showed lower hardening rate which is unexpected. EBSD micrographs and finite element analysis were used to investigate microstructural evolution and deformation condition around particles. It was concluded that particle fracture during deformation which is more expectable in larger particles, and also higher adiabatic heating in composite and not recrystallization related phenomena, are the main reasons for softening of stress flow curves at large deformation.

【 授权许可】

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