TY - JOUR
T1 - Atomistic modeling of the orientation-dependent pseudoelasticity in NiTi
T2 - Tension, compression, and bending
AU - Srinivasan, Prashanth
AU - Nicola, Lucia
AU - Simone, Angelo
PY - 2018
Y1 - 2018
N2 - Pseudoelasticity in NiTi shape memory alloy single crystals depends on the loading direction. Here, we present a comprehensive study in which molecular dynamics simulations of austenitic bulk single crystals under strain-controlled tensile and compressive loading along the 〈110〉,〈111〉 and 〈100〉 directions are performed, and the mechanical response of the crystals are contrasted. All simulations are performed using the MEAM interatomic potential proposed by Ko et al. (2015). The transformation strains and the Young's modulus of the initial austenitic and the final martensitic phases are compared with values obtained from the lattice deformation model and experimental results from the literature. Results show that depending on orientation the transformation occurs either through the formation of martensitic Lüders bands or through the transient formation of a multivariant martensite which, upon reorientation, becomes a dominant final single variant. Simulations are also performed to assess the orientation-dependent behavior of nano-wires subjected to bending, since the flexibility of the wires is orientation dependent.
AB - Pseudoelasticity in NiTi shape memory alloy single crystals depends on the loading direction. Here, we present a comprehensive study in which molecular dynamics simulations of austenitic bulk single crystals under strain-controlled tensile and compressive loading along the 〈110〉,〈111〉 and 〈100〉 directions are performed, and the mechanical response of the crystals are contrasted. All simulations are performed using the MEAM interatomic potential proposed by Ko et al. (2015). The transformation strains and the Young's modulus of the initial austenitic and the final martensitic phases are compared with values obtained from the lattice deformation model and experimental results from the literature. Results show that depending on orientation the transformation occurs either through the formation of martensitic Lüders bands or through the transient formation of a multivariant martensite which, upon reorientation, becomes a dominant final single variant. Simulations are also performed to assess the orientation-dependent behavior of nano-wires subjected to bending, since the flexibility of the wires is orientation dependent.
KW - Molecular dynamics
KW - Phase transformation
KW - Pseudoelasticity
KW - Shape-memory alloy
UR - http://www.scopus.com/inward/record.url?scp=85050146593&partnerID=8YFLogxK
U2 - 10.1016/j.commatsci.2018.07.028
DO - 10.1016/j.commatsci.2018.07.028
M3 - Article
AN - SCOPUS:85050146593
SN - 0927-0256
VL - 154
SP - 25
EP - 36
JO - Computational Materials Science
JF - Computational Materials Science
ER -