Analytical Modeling And Analysis.of Vibration Characteristic Of Hard-Coating Laminated Plate

Applying damping technology of hard coating to composite laminated plate is very promising,which has enormous advantages in keeping functioning in a expected way under the condition of high temperature and high corrosion.To effectively carry out this technology,dynamic model of hard-coating laminate composite structure is needed to analyze the damping mechanism of hard coating.In this paper,based on reasonably combining the isotropic hard coating and the anisotropic laminated plate and scientifically introducing mechanical characteristics of the hard coating,hard-coating laminate structure was chosen to investigate the method of building the dynamic model of hard-coating laminate composite structure and analyzing vibration characteristics.The details of research in this paper are as follows:(1)Based on the Classical Laminate Theory,the natural character of hard-coating laminate structure under free vibration has been analyzed.Orthogonal polynomials and beam functions are used to formulate the displacement field,Lagrange equation and Ritz method are also used to build the dynamic model of hard-coating laminated structure and obtain the natural characteristics.And then,ANSYS software is used for comparison and validation,and the results obtained improve the rationality of the developed analytical model and method.Moreover,based on the established model,the influences of hard-coating parameters,including thickness,Young's modulus and loss factor,on the vibration characteristics of the laminated plate are studied.(2)Based on the Classical Laminate Theory,the vibration response of hard-coating laminated structure under base excitation is analyzed.Complex modulus and orthogonal polynomials are used to introduce the parameters of hard coating and formulate the displacement field respectively,through which,Lagrange equation of this structure under base excitation is built.And then,the governing equation of forced vibration for the hard-coating laminated plate is obtained,and the harmonic response is solved using direct frequency domain method.In addition,the force and dynamic equibrium of the hard-coating laminated plate applied with external load are analyzed.Therefore,the governing equation of forced vibration in time domain for the plate acquired,the orthogonality of mode shapes and Duhamel integral are used to solve transient responses of the plate.At last,ANSYS software is used for comparison and validation,and the results obtained improve the rationality of the developed method of solving vibration response.What' s more,the influences of hard-coating parameters,including thickness,Young's modulus and loss factor,on the vibration responses of the laminated plate are studied.(3)To further the study about the influences of the hard coating on vibration character of laminated plate,the dynamic model of partially coated hard-coating laminated plate is built and the vibration character is analyzed.Based on equivalent single layer theory,energies of the partially coated hard-coating laminated plate are solved.Orthogonal polynomials are used to formulate the displacement field as well,and then,the governing equation of forced vibration for the partially coated hard-coating laminated plate is obtained by using Lagrange equation.Finally,natural frequencies,mode shapes and vibration responses are solved.Moreover,ANSYS software is used for comparison and validation,and the results obtained improve the rationality of the developed method.In addition,the influence of the coating area on the vibration characteristics of the partially coated hard-coating laminated plate is studied.(4)Taking the strain dependence of hard-coating materials into consideration,the analytical analysis of the laminated plate fully covered with hard coating is taken and the nonlinear governing equation is created.And then,Galerkin and Newton-Raphson method are used to present the method of solving resonant frequency and response of fixed frequency of the hard-coating laminated plate.Linear results are solved using the developed method,and results obtained by ANSYS software are used to validate the rationality of the mentioned method.This paper is able to provide reference for the application of hard-coating damping technology to laminated plate,and relevant methods and theories have significant reference value for the analysis of vibration character of laminated composite structure.