title: Elastocaloric effect in CuAlZn and CuAlMn shape memory alloys under compression.
abstract: This paper reports the elastocaloric effect of two Cu-based shape memory alloys: Cu68Al16Zn16 (CuAlZn) and Cu73Al15Mn12 (CuAlMn), under compression at ambient temperature. The compression tests were conducted at two different rates to approach isothermal and adiabatic conditions. Upon unloading at a strain rate of 0.1 s(-1) (adiabatic condition) from 4% strain, the highest adiabatic temperature changes (ΔTad) of 4.0 K for CuAlZn and 3.9 K for CuAlMn were obtained. The maximum stress and hysteresis at each strain were compared. The stress at the maximum recoverable strain of 4.0% for CuAlMn was 120 MPa, which is 70% smaller than that of CuAlZn. A smaller hysteresis for the CuAlMn alloy was also obtained, about 70% less compared with the CuAlZn alloy. The latent heat, determined by differential scanning calorimetry, was 4.3 J g(-1) for the CuAlZn alloy and 5.0 J g(-1) for the CuAlMn alloy. Potential coefficients of performance (COPmat) for these two alloys were calculated based on their physical properties of measured latent heat and hysteresis, and a COPmat of approximately 13.3 for CuAlMn was obtained.This article is part of the themed issue 'Taking the temperature of phase transitions in cool materials'.
authors.affiliation: Department of Refrigeration and Cryogenic Engineering, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi, People's Republic of China.
authors.forename: Suxin
authors.initials: S
authors.lastname: Qian
authors.affiliation: Department of Materials Science and Engineering, University of Maryland, College Park, MD, USA.
authors.forename: Yunlong
authors.identifier: 0000-0002-3590-4769
authors.initials: Y
authors.lastname: Geng
authors.affiliation: Department of Materials Science and Engineering, University of Maryland, College Park, MD, USA.
authors.forename: Yi
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Aerospace Engineering, University of Maryland, College Park, MD, USA.
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Pillsbury
authors.affiliation: Department of Pure and Applied Chemistry, Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba, Japan.
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Hada
authors.affiliation: Department of Pure and Applied Chemistry, Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Yamaguchi
authors.affiliation: Department of Pure and Applied Chemistry, Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba, Japan.
authors.forename: Kenjiro
authors.initials: K
authors.lastname: Fujimoto
authors.affiliation: Center for Environmental Energy Engineering, Department of Mechanical Engineering, University of Maryland, College Park, MD, USA.
authors.forename: Yunho
authors.initials: Y
authors.lastname: Hwang
authors.affiliation: Center for Environmental Energy Engineering, Department of Mechanical Engineering, University of Maryland, College Park, MD, USA.
authors.forename: Reinhard
authors.initials: R
authors.lastname: Radermacher
authors.affiliation: Department of Materials Science and Engineering, Iowa State University, Ames, IA, USA.
authors.forename: Jun
authors.initials: J
authors.lastname: Cui
authors.affiliation: Japan Copper Development Association, Tokyo, Japan.
authors.forename: Yoji
authors.initials: Y
authors.lastname: Yuki
authors.affiliation: Shinko Metal Products Co. Ltd, Fukuoka, Japan.
authors.forename: Koutaro
authors.initials: K
authors.lastname: Toyotake
authors.affiliation: Department of Materials Science and Engineering, University of Maryland, College Park, MD, USA takeuchi@umd.edu.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Takeuchi
keywords: CuAlMn; CuAlZn; elastocaloric effect; refrigeration; shape memory alloy