Nanocrystallization of NiTi shape memory alloys made amorphous by high-pressure torsion

Author(s)
Martin Peterlechner, Thomas Waitz, Hans-Peter Karnthaler
Abstract

Almost complete amorphization is obtained in NiTi subjected to high-pressure torsion (HPT). Nanocrystallization occurs more than 100 °C lower than in amorphous sputtered and melt spun NiTi. This is caused by medium-range-ordered debris surviving HPT and triggering nanocrystallization. A high nucleation rate and low growth rate result from in situ heating transmission electron microscopy experiments. The kinetics of the heterogeneous nanocrystallization differs significantly from that leading to coarse grains. Therefore, HPT allows the nanostructure to be tailored to enhance shape memory properties. © 2008 Acta Materialia Inc.

Organisation(s)
Physics of Nanostructured Materials
Journal
Scripta Materialia
Volume
59
Pages
566-569
No. of pages
4
ISSN
1359-6462
DOI
https://doi.org/10.1016/j.scriptamat.2008.05.004
Publication date
2008
Peer reviewed
Yes
Austrian Fields of Science 2012
103018 Materials physics
Portal url
https://ucris.univie.ac.at/portal/en/publications/nanocrystallization-of-niti-shape-memory-alloys-made-amorphous-by-highpressure-torsion(2f0d21b4-9905-4a9d-9968-c2d2bda7dae1).html