Micromechanical Behaviorof Multilayered Ti/Nb Composites Processed by Accumulative Roll Bonding: An in-situ Synchrotron X-ray Diffraction Investigation

Published

February 14, 2021

Author(s)

S. Jiang, R. L. Peng, Z. Hegedus, Thomas Gnaupel-Herold, J. J. Moverare, U. Lienert, F. Fang, X. Zhao, L. Zuo, N. Jia

Abstract

Ti/Nb multilayered composites were fabricated by accumulative roll bonding (ARB). With increasing ARB cycles, shear bands become predominant in the continuously strengthened composites. The correlation between micromechanical behavior and mechanical properties of the composites with different lamellar morphologies were elucidated by in-situ high-energy X-ray diffraction tensile tests. The results show that the rapid strengthening of the composites at high ARB cycles mainly originates from the Nb layers which are strengthened by the interfaces. The softer Ti grains show a slow decline of strain hardening during plastic deformation, which extends strain hardening of the composites to a wide range and postpones the onset of necking. Furthermore, for the first time, we obtain the complete stress state of the multilayered structure under strong constraints of the interfaces. In the multilayers featured with shear bands, significant load partitioning between the neighboring constituents leads to complex triaxial stresses in each metal and dislocations tend to slip along the shear direction. This promotes dislocation multiplication and motion and thus is conductive to strength enhancement of the composites, while a satisfactory ductility is still maintained. The present work provides a fundamental understanding of load partitioning and strengthening mechanisms of the multilayers processed by multiple ARB cycles.

Citation

Acta Materialia

Volume

205

Pub Type

Journals

Download Paper

https://doi.org/10.1016/j.actamat.2020.116546

Local Download

Keywords

Ti/Nb multilayers, micromechanical behavior, high-energy X-ray37 diffraction, lattice strain, load partitioning

Citation

Jiang, S. , Peng, R. , Hegedus, Z. , Gnaupel-Herold, T. , Moverare, J. , Lienert, U. , Fang, F. , Zhao, X. , Zuo, L. and Jia, N. (2021), Micromechanical Behaviorof Multilayered Ti/Nb Composites Processed by Accumulative Roll Bonding: An in-situ Synchrotron X-ray Diffraction Investigation, Acta Materialia, [online], https://doi.org/10.1016/j.actamat.2020.116546, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=930775 (Accessed April 29, 2024)