Analysis Of Bending Deformation Characteristics Of Shape Memory Alloy Beams

As a new type of intelligent material,shape memory alloy has been widely studied because of its super-elasticity and shape memory effect.It is found that these two special properties are related to the phase transformation which is induced by stress and temperature.In order to explore the effect of mechanical load,temperature and volume fraction of shape memory alloy on this phase transformation,further study can focus on the bending deformation characteristics of shape memory alloy beam under different conditions.First,this essay is based on the existing stress-strain relationship of shape memory alloys,the bending deformation theory,and the assumption of the flat section.The normal stress distribution in cross-section,neutral axis position,curvature,and phase change boundary along the axial direction can be obtained by solving the equilibrium equation,after introducing the tension-compression asymmetry coefficient.Additionally,it analyzes the effect of the tension-compression asymmetry coefficient and mechanical load on the bending deformation.The result is consistent with previous research.Second,based on the relationship between critical stress and temperature of a shape memory alloy,this essay discusses the influence of temperature and tension-compression asymmetry coefficient on the bending deformation,and obtains the relationship between the normal stress distribution and temperature and the tension-compression asymmetry coefficient.Furthermore,it analyzes the influence on the distribution of phase change region,neutral axis position,curvature and phase boundary along the axial direction at different temperatures and the tension-compression asymmetry coefficient.Finally,ignoring the mechanical load and temperature changes,this essay reveals the effect of the volume fraction of shape memory alloy and the tension-compression asymmetry coefficient on the bending deformation of the functionally graded shape memory alloy beam.According to the normal stress distribution in each phase change stage,it can be obtained about the influence of the power exponent and the tension-compression asymmetry coefficient on the phase change region,neutral axis position,curvature and phase boundary along the axial direction,by solving the equilibrium equation.These results have a positive effect on the research of the bending problem of shape memory alloy beams,and also they have some reference value for the practical application of engineering.