Orientation, Size, and Temperature Dependent Ductile Brittle Transition in NiAl Nanowire under Tensile Loading - A Molecular Dynamics Study

  • V. K. Sutrakar Aeronautical Development Establishment, Bangalore
  • A. C.R. Pillai Aeronautical Development Establishment, Bangalore
  • D. Roy Mahapatra Indian Institute of Science, Bangalore
Keywords: Intermetallic compounds, nanostructurs, molecular dynamics, mechanical properties, phase transitions, ductile brittle transition temperature.

Abstract

In the present paper, thermo-mechanical response of B2-NiAl nanowire along the <100>, <110>, and <111> orientations has been studied using molecular dynamics simulations. Nanowire with cross-sectional dimensions of ~20x20 Å2, ~25x25 Å2, and ~30x30 Å2 and temperature range of 10 K-900 K has been considered. A Combined effect of size, orientation, and temperature on the stress-strain behavior under uniaxial tensile loading has been presented. It has been observed that <111> oriented NiAl nanowire that is energetically most stable gives highest yield stress which further reduces with <110> and <100> orientations. A remarkable ductile brittle transition (DBT) with an increase in temperature has also been reported for all the orientations considered in the present study. The DBT observed for the nanowire has also been compared with the reported DBT of bulk B2-NiAl obtained from experiments. Alternate technique has also been proposed to increase the toughness of a given material especially at lower temperature regions, i.e. below DBT.

Defence Science Journal, 2014, 64(2), pp. 179-185. DOI: http://dx.doi.org/10.14429/dsj.64.4310

Author Biographies

V. K. Sutrakar, Aeronautical Development Establishment, Bangalore
Dr Vijay Kumar Sutrakar obtained his MTech (Design Engineering) from Indian Institute of Technology, New Delhi, and PhD (Computational Mechanics of Nanomaterials) Indian Institute of Science, Bangalore in 2004, and 2013, respectively. He is Scientist ‘D’ at Aeronautical Development Establishment, Bangalore. He has published more than 40 papers in the international journals/ conferences in the area of finite element, computational mechanics, computational material science, computational electromagnetic, nanomaterials, and nanotechnology.
A. C.R. Pillai, Aeronautical Development Establishment, Bangalore
Dr A.C. Radhakrishna Pillai obtained his MSc (Maths) from IIT, Kanpur and PhD (Maths) from IIT, Delhi. He is currently Scientist ‘g’ and Head, Applied Research Division and group Director (AwS) at Aeronautical Development Establishment,  Bangalore. His current research interests are in the areas of computational fluid dynamics, numerical design optimization, and computational electromagnetics.
D. Roy Mahapatra, Indian Institute of Science, Bangalore
Prof. D. Roy Mahapatra obtained his PhD (Aerospace Engineering) from IISc Bangalore, India, in 2004. He is a faculty member with Department of Aerospace Engineering, Indian Institute of Science Bangalore. His research interests are mechanics of materials, mathematical modeling, smart materials for sensors and actuator applications, integrated nano and micro-scale systems dynamics and their applications in health monitoring, diagnostics of materials and structures.
Published
2014-03-20
How to Cite
Sutrakar, V., Pillai, A., & Mahapatra, D. (2014). Orientation, Size, and Temperature Dependent Ductile Brittle Transition in NiAl Nanowire under Tensile Loading - A Molecular Dynamics Study. Defence Science Journal, 64(2), 179-185. https://doi.org/10.14429/dsj.64.4310
Section
Materials Science & Metallurgy