Thermal Buckling of Laminated Composite Beams with Embedded Shape Memory Alloy Actuators

Abstract

In this paper, the thermal buckling and postbuckling behaviours of a composite beam with embedded shape memory alloy (SMA) wires are investigated experimentally and analytically. For the purpose of enhancing the critical buckling temperature and reduction of the lateral deflection on thermal buckling and postbuckling, the characteristics of thermal buckling are investigated through the use of the shape recovery force. The results of thermal buckling tests using uniformly heated and clamped composite beam specimens with embedded SMA wire actuators are discussed. The temperature-load-deflection behaviour records present quantitatively how the shape recovery force affects the thermal buckling behaviour. For this experiment, we considered the initial geometric imperfections, the slenderness ratio of the beam and the embedding position of the SMA wire actuators. The experimental results show that the shape recovery force reduces the thermal expansion of the composite laminated beam. This results in an increase of the critical buckling temperature and a reduction of the lateral deflection of the beams.

Exact solution for nonlinear thermal stability of hybrid laminated composite Timoshenko beams reinforced with SMA fibers

“…When the assumption of temperature dependency is established, critical buckling temperatures are a little The total end-shortening force and bending moment of SMA hybrid composite beams as a function of uniform temperature rise for the C-C boundary conditions are plotted in Figures (6) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 27 and (7), respectively. The geometry and properties of the beam are the same with those used in Figure (5). As seen, bifurcation points are detectable through the end-shortening forcetemperature or bending moment-temperature graphs.…”

“…They also considered the influence of initial imperfections on the post-buckling equilibrium path of the beam incorporated with SMA wires [5]. Similar to the case of an initially flat beam, for geometrically imperfect ones, the study concluded in the high capability of SMA actuators in reduction of the lateral deflection at a certain temperature.…”

“…Motivated by experimentally observed results of Chio et al [4,5], Thompson and Loughlan [9] and Loughlan et al [10] or the simulation-based conclusion of Lee and his co-authors [6,7,8] many investigations have been conducted to study the mechanism and the influence of SMA actuators on postponing the bifurcation points, limit points, and enhancing the post-critical states of the structures embedded with SMA wires. Ostachowicz et al [11,12] investigated the linear problems of free vibration, thermal buckling, and flutter in delaminated composite plate embedded with SMA fibers using the finite element method.…”

Stability Control of Active Compressed Rods with Shape Memory Polymers

“…Let ε and k denote the strain and change of curvature-twist vectors, respectively, and let u designate the displacement vector; then the linear kinematic relation can be expressed as (3) and (4) where s represents the length coordinate along the rod; and t is the unit tangent vector.…”

“…Optical fibers have been used to detect the buckling event in cylindrical shells [2]. Experimental investigation has been carried out on the buckling control of composite beams with embedded Shape Memory Alloys (SMA) [3,4]. This work aims at a theoretical treatment of the stability control of axially compressed elastic rods with the help of metallic or polymeric SMMS.…”