Thermomechanical characterization of NiTiCu and NiTi SMA actuators: influence of plastic strains

abstract

• The focus of this study is the thermomechanical characterization and comparison between two different shape memory alloys (SMAs) quantifying the effect of plastic strain on the transformation characteristics of SMA actuators. In this study, the thermomechanical response and transformation characteristics of a NiTiCu and a NiTi SMA are studied as a function of the induced plastic strain for four different loading paths: (1) an elastic-plastic loading of the austenitic phase, (2) a stress-induced martensitic phase transformation, (3) an elastic-detwinning-plastic loading of the martensitic phase and (4) a thermally-induced phase transformation under a constant applied stress. Each loading path is repeated multiple times, with an incremental change of the total applied strain, to determine the effect of accumulated plastic strain on the phase transformation characteristics of the two SMA material systems. The effects of plastic strain are quantified by measurements of recoverable strain during a thermal cycle under zero applied stress, measurements of heat of transformation from a differential scanning calorimeter and microstructural evaluations.

authors

• Lagoudas, Dimitris

published proceedings

• SMART MATERIALS & STRUCTURES

author list (cited authors)

• Miller, D. A., & Lagoudas, D. C.

citation count

• 105

complete list of authors

• Miller, DA||Lagoudas, DC

publication date

• October 2000

publisher

• IOP Publishing  Publisher

published in

• Smart Materials and Structures  Journal

keywords

• 40 Engineering
• 4016 Materials Engineering

Digital Object Identifier (DOI)

• 10.1088/0964-1726/9/5/308

start page

• 640

end page

• 652

volume

• 9

issue

• 5

URL

• http%3A%2F%2Fdx.doi.org%2F10.1088%2F0964-1726%2F9%2F5%2F308