Carbon nanotubes enhanced bimorph effect of U-shaped flexure cantilever beam actuators made from polyethylene terephthalate and polymethyl methacrylate

Abstract

U-shaped cantilever actuators made from PET and PMMA exhibit a bimorph effect upon radiation heating and beam always moves toward PMMA side with maximum displacement and displacing rate measured to be 2100 μm and 35 μm s⁻¹. This number increases to 3300 μm and 55 μm s⁻¹ while PET surfaces are coated with single-walled carbon nanotubes acting as heat reservoir. Actuations can be further improved by carbon nanotube resistive heating and improvement reaches two-fold (4100 μm and 68.3 μm s⁻¹). Coated beam actuators exhibit an excellent stability over 2 h intermittent operations where the maximum displacement varies only in ±1%.