Deformation behavior of a NiCo multilayer with a modulated grain size distribution

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

卷:641

Article

Daly, Matthew¹  McCrea, Jonathan Lawrence²  Bouwhuis, Brandon Andrew²  Singh, Chandra Veer¹  Hibbard, Glenn David¹ 

[1] Univ Toronto, Dept Mat Sci & Engn, Toronto, ON M5S 3E4, Canada

[2] Integran Technol Inc, Mississauga, ON L4V 1H7, Canada

关键词: Cellular materials;    Nanostructured materials;    Plasticity;    Fracture;    Mechanical characterization;   

DOI  :  10.1016/j.msea.2015.06.049

来源: Elsevier

【 摘 要 】

In order to gain a fundamental understanding of the deformation behavior of multilayer architectures composed of a periodic layering of hard and soft structural features, NiCo samples possessing modulated nanocrystalline and coarse-grained microstructures were fabricated using pulsed electrodeposition. Scanning electron microscopy imaging confirmed that the samples possessed an alternating grain size distribution and the desired 1:1 thickness ratio of constitutive layers. Uniaxial tensile testing showed a rule of mixtures relationship in yield and ultimate tensile strengths for the multilayer with respect to reference samples. Notably, an increase in elongation to failure was observed in the multilayer when compared to the nanocrystalline reference. The gains in elongation were found to be associated with improved neck stability due to dislocation activity within the coarse-grained layers. The morphology of the fracture surface, considered together with the available mechanical data, electron micrographs and texture measurements, forms the basis of a multiscale deformation mechanism which describes a failure pathway for multilayer architectures with nanocrystalline and coarse-grained structural features. (C) 2015 Elsevier B.V. All rights reserved.

【 授权许可】

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