The Research On Characteristics Of Elastic Waves Propagation In The Functionally Graded Material Plate

The concept of functionally graded material is proposed in80years of20century. Then, along with scientific research and industrial development of aerospace industry etc, the application of FGM is increasingly. New demand is put forward about correlated modern analysis for undamaged detection of functionally graded material plate. It is necessary to grasp the characteristic of elastic waves propergation in the functionally graded material. The characteristic of elastic wave propergation in the FGM plate is the main parts of inverstigation in this paper. The following contents are mainly discussed in this paper:The developed history and recent developments of functionally graded material are reviewed in the first chapter. The researchful achievement and existential problem at present are pointed out. The main contents of researching are determined in this thesis.The design method of mechanics parametric about functionally graded material are introduced in the secend chapter, A set of the elastic dynamic equations of wave propagation in the inhomogeneous material is derived. The fundamental analysis methods about wave propagation in FGM plate, including the method of Transfer Matrix, the method of finite element, the method of WKBJ, are discussed.The characteristic of SH wave propagation in inhomogeneous FGM plate are studied in the third chapter. The dispersion relations of SH wave propagation in the functionally graded material plate are obtained by using the method of WKBJ. The approximate analytical solution of SH wave propagation in the FGM plate is derived. The method of numerical calculation is provided. An example of FGM plate in engineering, the dispersion relations of SH wave propagation in the FGM plate with different material parameters are studied. And the displacement curves along the cross section are plotted.The characteristic of P and SV coupled wave propagation in inhomogeneous FGM plate are discussed in the fourth chapter. The dispersion relations of the P and SV coupled wave propagation in the functionally graded material plate are obtained by using the method of WKBJ. The approximate analytical solution of PSV coupled wave’s propagation in FGM plate is derived. The method of numerical calculation is provided. An example of FGM plate in engineering, the dispersion relations of P and SV coupled wave propagation in the FGM plate with different material parameters are studied. And the displacement curves along the cross section are plotted. These conclusions in the paper will be of reference value for the analysis of dynamic response of wave propagation in the functionally graded material plate and the nondestructive examination of the functionally graded material.