Experimental characterization of the thermo-electro-mechanical properties of a shape memory composite during electric activation. (1st September 2022)

• Record Type: Journal Article
• Authors: Pereira Sánchez, Clara; Houbben, Maxime; Fagnard, Jean-Francois; Harmeling, Pascal; Jérôme, Christine; Noels, Ludovic; Vanderbemden, Philippe
• Is Part Of: Smart materials and structures. Volume 31:Number 9(2022)
• Publication Date: 2022-09-01
• Subjects: shape-memory -- two-way shape memory -- composites -- carbon nanotubes -- resistive heating -- electroactivation; Smart materials -- Periodicals; Strucural design -- Periodicals; 620.11
• DOI: 10.1088/1361-665X/ac8297
• Languages: English
• ISSNs: 0964-1726

Abstract

Abstract: This works investigates in detail the electro-thermo-mechanical properties of a shape memory composite (SMC) during shape memory cycles in which the heating is a result of resistive heating. The SMC is a covalently cross-linked poly( ϵ -caprolactone) network filled with 3 wt% of multiwall carbon nanotubes. The characterization is performed with the help of a custom-made tensile test bench that is able to couple the mechanical characterization with the thermal and electrical ones. A proportional integral controller using the lambda tuning method is used in order to control the temperature achieved by resistive heating of the SMC. The electrical resistivity of the SMC shows a non-linear and non-monotonic dependence on temperature and strain. The resistivity is also found to vary among successive shape memory cycles, suggesting that a (first) training cycle is necessary not only to stabilize the mechanical but also the electrical properties of the SMC. A fuzzy logic controller for constant load control is also used to investigate the strain variation with temperature related to the two-way shape memory effect of the SMC. The results give evidence of the strong interplay between the electrical and (thermo-)mechanical characteristics of electroactive SMCs.