Abstract: As a new type of intelligent elements, the shape memory alloy (SMA) beam are applied widely in the engineering field. Based on experimental stress-strain curves of superelastic SMA and the large deformation theory of beams, considering the different properties between tension and compression and the end-moving, the nonlinear bending deformation equations of SMA beam are established. Meanwhile the shooting method and Simpson’s numerical integral method are adopted. Through the deflection lines under different load condition and the maximum deflection-bending moment curve, the effects of material nonlinearity, geometric nonlinearity and the end-moving on bending deformation of SMA beam are investigated. The results show that the neutral layer of beam changes with bending moment. If the bending moment is small, the material property is linear, the geometry nonlinear and the end-moving almost have no effect on deflection deformation of beam. If the bending moment is higher, the material property is nonlinear, the geometry nonlinear and the end-moving have noticeable effect on deflection deformation of beam.

Key words: Nonlinear bending, Shape memory alloy beam, Shooting method