Texture, strain, and phase-fraction measurements during mechanical cyclingin superelastic NiTi

Citation
R. Vaidyanathan et al., Texture, strain, and phase-fraction measurements during mechanical cyclingin superelastic NiTi, MET MAT T A, 32(3A), 2001, pp. 777-786
Citations number
32
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science",Metallurgy
Journal title
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
ISSN journal
10735623 → ACNP
Volume
32
Issue
3A
Year of publication
2001
Pages
777 - 786
Database
ISI
SICI code
1073-5623(200103)32:3A<777:TSAPMD>2.0.ZU;2-5
Abstract
Superelastic NiTi was subjected to simultaneous neutron diffraction and uni axial compressive cycling between 10 and 980 MPa. The objective was an in-s itu investigation of the evolution of the stress-induced, reversible transf ormation between austenite and martensite, to determine the cause of the ch anges in the macroscopic stress-strain response with cycling. Rietveld refi nement was used to analyze the neutron spectra and quantify the phase fract ion, texture, and elastic strain. The average phase strain in the mechanica lly loaded austenite (at a given stress) remained unaltered during the 100 load-unload cycles. However, differences in both the volume fraction and te xture of austenite and martensite were noted as cycling progressed, suggest ing that these factors are responsible for the changes in the macroscopic s tress-strain response of NiTi with mechanical cycling.