A Caltech Library Service

Temperature-induced shape morphing of bi-metallic structures

Taniker, S. and Cellia, P. and Pasini, D. and Hofmann, D. C. and Daraio, C. (2020) Temperature-induced shape morphing of bi-metallic structures. International Journal of Solids and Structures, 190 . pp. 22-32. ISSN 0020-7683.

[img] PDF - Submitted Version
See Usage Policy.


Use this Persistent URL to link to this item:


In this work, we study the thermo-mechanical behavior of metallic structures designed to significantly change shape in response to thermal stimuli. This behavior is achieved by arranging two metals with different coefficient of thermal expansion (CTE), Aluminum and Titanium, as to create displacement-amplifying units that can expand uniaxially. In particular, our design comprises a low-CTE bar surrounded by a high-CTE frame that features flexure hinges and thicker links. When the temperature increases, the longitudinal expansion of the high-CTE portion is geometrically constrained by the low-CTE bar, resulting in a large tangential displacement. Our design is guided by theoretical models and numerical simulations. We validate our approach by fabricating and characterizing individual units, one dimensional arrays and three-dimensional structures. Our work shows that structurally robust metallic structures can be designed for large shape changes. The results also demonstrate how harsh environmental conditions (e.g., the extreme temperature swings that are characteristic of extraterrestrial environments) can be leveraged to produce function in a fully passive way.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Daraio, C.0000-0001-5296-4440
Additional Information:© 2019 Elsevier Ltd. Received 6 August 2019, Revised 3 October 2019, Accepted 23 October 2019, Available online 24 October 2019. This research was carried out at the California Institute of Technology and the Jet Propulsion Laboratory under a contract with the National Aeronautics and Space Administration, and funded through the President’s and Director’s Fund Program. S.T. acknowledges the support of Roketsan. P.C. and C.D. acknowledge support from the Foster and Coco Stanback Space Innovation Fund. The authors wish to thank Fernando Garza for his fabrication efforts, Christina Naify and Terry Gdoutos for useful discussions.
Funding AgencyGrant Number
JPL President and Director's FundUNSPECIFIED
Foster and Coco Stanback Postdoctoral FellowshipUNSPECIFIED
Subject Keywords:Adaptive structures; Architected solids; Extreme thermal expansion; Displacement amplification mechanisms; Environment-triggered morphing; Space structures
Record Number:CaltechAUTHORS:20191024-101104702
Persistent URL:
Official Citation:S. Taniker, P. Celli, D. Pasini, D.C. Hofmann, C. Daraio, Temperature-induced shape morphing of bi-metallic structures, International Journal of Solids and Structures, Volume 190, 2020, Pages 22-32, ISSN 0020-7683, (
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:99434
Deposited By: Tony Diaz
Deposited On:24 Oct 2019 17:18
Last Modified:12 Feb 2020 18:03

Repository Staff Only: item control page