Multiaxial stress-strain response and displacive transformations in NiTi alloy from first principles

Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26620%2F16%3APU118126" target="_blank" >RIV/00216305:26620/16:PU118126 - isvavai.cz</a>
Result on the web
<a href="http://dx.doi.org/10.1016/j.actamat.2016.02.043" target="_blank" >http://dx.doi.org/10.1016/j.actamat.2016.02.043</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1016/j.actamat.2016.02.043" target="_blank" >10.1016/j.actamat.2016.02.043</a>

Result language
angličtina
Original language name
Multiaxial stress-strain response and displacive transformations in NiTi alloy from first principles
Original language description
Present ab initio study was focussed on a response of NiTi martensite to a superposition of shear and tensile or compressive stresses acting normally to the shear planes. The theoretically predicted basecentered orthorhombic (BCO) ground-state structure was found unstable under uniaxial compression and two transformations, one from orthorhombic to a monoclinic symmetry and the other back from monoclinic to orthorhombic symmetry, were observed in the computational model. The former transformation shows that the uniaxial compressive stress of about 4 GPa destabilizes the BCO structure by reducing its symmetry to the experimentally observed monoclinic one. However, superposition of small shear stresses remarkably lowers the compressive stress necessary for this destabilization. The latter transformation then draws the crystal lattice to the B19 structure. The theoretical shear strength of NiTi martensite was subsequently computed as a function of the normal stress. The results obtained show that the effect of the normal stress is surprisingly opposite to that calculated for NiTi austenite and other cubic metals, i.e., that the shear strength is lowered by the compressive normal stress and vice versa.
Czech name
—
Czech description
—

Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
—
OECD FORD branch
10302 - Condensed matter physics (including formerly solid state physics, supercond.)

Project
Result was created during the realization of more than one project. More information in the Projects tab.
Continuities
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year
2016
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Similar results(10)