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Title: Narrow thermal hysteresis of NiTi shape memory alloy thin films with submicrometer thickness

Abstract

NiTi shape memory alloy (SMA) thin films were fabricated using biased target ion beam deposition (BTIBD), which is a new technique for fabricating submicrometer-thick SMA thin films, and the capacity to exhibit shape memory behavior was investigated. The thermally induced shape memory effect (SME) was studied using the wafer curvature method to report the stress-temperature response. The films exhibited the SME in a temperature range above room temperature and a narrow thermal hysteresis with respect to previous reports. To confirm the underlying phase transformation, in situ x-ray diffraction was carried out in the corresponding phase transformation temperature range. The B2 to R-phase martensitic transformation occurs, and the R-phase transformation is stable with respect to the expected conversion to the B19′ martensite phase. The narrow hysteresis and stable R-phase are rationalized in terms of the unique properties of the BTIBD technique.

Authors:
; ;  [1]
  1. Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States)
Publication Date:
OSTI Identifier:
22592852
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films; Journal Volume: 34; Journal Issue: 5; Other Information: (c) 2016 American Vacuum Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 42 ENGINEERING; CAPACITY; DEPOSITION; HYSTERESIS; ION BEAMS; MARTENSITE; MARTENSITIC STEELS; NICKEL ALLOYS; PHASE TRANSFORMATIONS; SHAPE MEMORY EFFECT; STRESSES; TEMPERATURE RANGE 0273-0400 K; THICKNESS; THIN FILMS; TITANIUM ALLOYS; X-RAY DIFFRACTION

Citation Formats

Hou, Huilong, Hamilton, Reginald F., E-mail: rfhamilton@psu.edu, and Horn, Mark W.. Narrow thermal hysteresis of NiTi shape memory alloy thin films with submicrometer thickness. United States: N. p., 2016. Web. doi:10.1116/1.4959567.
Hou, Huilong, Hamilton, Reginald F., E-mail: rfhamilton@psu.edu, & Horn, Mark W.. Narrow thermal hysteresis of NiTi shape memory alloy thin films with submicrometer thickness. United States. doi:10.1116/1.4959567.
Hou, Huilong, Hamilton, Reginald F., E-mail: rfhamilton@psu.edu, and Horn, Mark W.. 2016. "Narrow thermal hysteresis of NiTi shape memory alloy thin films with submicrometer thickness". United States. doi:10.1116/1.4959567.
@article{osti_22592852,
title = {Narrow thermal hysteresis of NiTi shape memory alloy thin films with submicrometer thickness},
author = {Hou, Huilong and Hamilton, Reginald F., E-mail: rfhamilton@psu.edu and Horn, Mark W.},
abstractNote = {NiTi shape memory alloy (SMA) thin films were fabricated using biased target ion beam deposition (BTIBD), which is a new technique for fabricating submicrometer-thick SMA thin films, and the capacity to exhibit shape memory behavior was investigated. The thermally induced shape memory effect (SME) was studied using the wafer curvature method to report the stress-temperature response. The films exhibited the SME in a temperature range above room temperature and a narrow thermal hysteresis with respect to previous reports. To confirm the underlying phase transformation, in situ x-ray diffraction was carried out in the corresponding phase transformation temperature range. The B2 to R-phase martensitic transformation occurs, and the R-phase transformation is stable with respect to the expected conversion to the B19′ martensite phase. The narrow hysteresis and stable R-phase are rationalized in terms of the unique properties of the BTIBD technique.},
doi = {10.1116/1.4959567},
journal = {Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films},
number = 5,
volume = 34,
place = {United States},
year = 2016,
month = 9
}
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