Tensile deformation of NiTi wires.

Published

Journal Article

We examine the structure and properties of cold drawn Ti-50.1 at % Ni and Ti-50.9 at % Ni shape memory alloy wires. Wires with both compositions possess a strong <111> fiber texture in the wire drawing direction, a grain size on the order of micrometers, and a high dislocation density. The more Ni rich wires contain fine second phase precipitates, while the wires with lower Ni content are relatively free of precipitates. The wire stress-strain response depends strongly on composition through operant deformation mechanisms, and cannot be explained based solely on measured differences in the transformation temperatures. We provide fundamental connections between the material structure, deformation mechanisms, and resulting stress-strain responses. The results help clarify some inconsistencies and common misconceptions in the literature. Ramifications on materials selection and design for emerging biomedical applications of NiTi shape memory alloys are discussed.

Full Text

Duke Authors

Cited Authors

  • Gall, K; Tyber, J; Brice, V; Frick, CP; Maier, HJ; Morgan, N

Published Date

  • December 2005

Published In

Volume / Issue

  • 75 / 4

Start / End Page

  • 810 - 823

PubMed ID

  • 16138359

Pubmed Central ID

  • 16138359

Electronic International Standard Serial Number (EISSN)

  • 1552-4965

International Standard Serial Number (ISSN)

  • 1549-3296

Digital Object Identifier (DOI)

  • 10.1002/jbm.a.30464

Language

  • eng