Recovery stress behavior of Fe-SMA under fatigue and thermal loading

authored by: Zhen Yu Chen, Xiang Lin Gu, Malte Vollmer, Thomas Niendorf, Elyas Ghafoori, Qian Qian Yu
Abstract: The present paper investigates mechanical properties and recovery stress behavior of an iron-based shape memory alloy (Fe-SMA) with a special focus on the effect of fatigue and thermal loading. Change in recovery stress of activated Fe-SMAs subjected to fatigue at RT, −20 °C, 60 °C, and −20 to 60 °C was monitored. A second activation after fatigue was performed to investigate the retrievability of the lost recovery stress owing to fatigue. Coefficients of thermal expansion (CTEs) of the samples with different activation histories were also calculated. Results showed that the maximum reduction in recovery stress after two million cyclic loads of Δɛ=0.070% was approximately 20% under RT and −20 °C. A high temperature (60 °C) weakened such detrimental effect owing to higher critical stresses for martensitic transformation at higher temperatures, leading to only 10% reduction in recovery stress. Loss in the recovery stress due to fatigue was pronouncedly retrieved by a reactivation regardless of the temperature scenarios. This study extends understanding of recovery stress behavior of Fe-SMAs subjected to fatigue and thermal loading, and explores the retrievability of relaxed recovery stress by a second activation.
Organisation(s): Institute of Steel Construction
External Organisation(s): Tongji University
University of Kassel
Type: Article
Journal: Thin-walled structures
Volume: 188
ISSN: 0263-8231
Publication date: 07.2023
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Civil and Structural Engineering, Building and Construction, Mechanical Engineering
Electronic version(s): https://doi.org/10.1016/j.tws.2023.110799 (Access: Closed)

BibTeX

@article{aff2cade4e794230a5cfb22e9b14f793,
title = "Recovery stress behavior of Fe-SMA under fatigue and thermal loading",
abstract = "The present paper investigates mechanical properties and recovery stress behavior of an iron-based shape memory alloy (Fe-SMA) with a special focus on the effect of fatigue and thermal loading. Change in recovery stress of activated Fe-SMAs subjected to fatigue at RT, −20 °C, 60 °C, and −20 to 60 °C was monitored. A second activation after fatigue was performed to investigate the retrievability of the lost recovery stress owing to fatigue. Coefficients of thermal expansion (CTEs) of the samples with different activation histories were also calculated. Results showed that the maximum reduction in recovery stress after two million cyclic loads of Δɛ=0.070% was approximately 20% under RT and −20 °C. A high temperature (60 °C) weakened such detrimental effect owing to higher critical stresses for martensitic transformation at higher temperatures, leading to only 10% reduction in recovery stress. Loss in the recovery stress due to fatigue was pronouncedly retrieved by a reactivation regardless of the temperature scenarios. This study extends understanding of recovery stress behavior of Fe-SMAs subjected to fatigue and thermal loading, and explores the retrievability of relaxed recovery stress by a second activation.",
keywords = "Fatigue, Iron-based shape memory alloy, Reactivation, Recovery stress, Thermal loading",
author = "Chen, {Zhen Yu} and Gu, {Xiang Lin} and Malte Vollmer and Thomas Niendorf and Elyas Ghafoori and Yu, {Qian Qian}",
note = "Funding Information: This study was supported by the National Natural Science Foundation of China (Project Nos. 52222803 , 51938013 and 51878485 ) and National Key R&D Program of China ( 2022YFC3803000 ). We also thank re-fer AG in Switzerland for providing Fe-SMA materials. ",
year = "2023",
month = jul,
doi = "10.1016/j.tws.2023.110799",
language = "English",
volume = "188",
journal = "Thin-walled structures",
issn = "0263-8231",
publisher = "Elsevier Ltd.",
}