功能梯度板中的波

发布时间：2018-04-15 17:13

本文选题：功能梯度材料 + 无损检测　；参考：《石家庄铁道大学》2016年硕士论文

【摘要】：随着科学技术的发展,功能梯度材料作为一种新型材料的出现,大大推动了经济社会的发展,功能梯度材料具有良好的现实应用性能。波在其中的传播特性和力学性能研究越来越受到人们的重视,广泛被国内外学者研究。功能梯度材料在航天工程、机械工程、能源工程、电子工程、建筑工程、生物医学工程等高端科学领域已经得到了广泛的应用。功能梯度材料作为一种波导,因此可以借助于波在其中的传播特性对梯度材料进行无损检测。基于这一原理进行展开研究的,简要概述如下:首先应用级数展开迭代法对应力波在功能梯度材料中的传播进行实例计算,讨论了应力波在频率域和时间域内的传播特性及梯度系数变化对频散特性的影响。其次应用变分法对Love波在功能梯度材料结构中传播特性进行了研究,推导了Love波在功能梯度材料中的频散关系方程式,结合具体算例讨论了厚度对Love波频散特性的影响,与精确解相对比证明了该理论的正确性。最后研究了PSV耦合波在功能梯度板中的传播特性。分别讨论了无限厚度情况下功能梯度板中瑞利波传播特性和有限厚度情况下Lamb波的正反模态传播特性。本研究有助于功能梯度材料的无损检测、矿产资源的勘测及地震数据的预测,同时为功能梯度材料的优化和设计提供理论帮助。
[Abstract]:With the development of science and technology, functionally graded materials (FGM), as a new type of materials, have greatly promoted the development of economy and society.More and more attention has been paid to the study of wave propagation characteristics and mechanical properties, and has been widely studied by scholars at home and abroad.Functionally graded materials (FGM) have been widely used in aerospace engineering, mechanical engineering, energy engineering, electronic engineering, architectural engineering, biomedical engineering and other high-end science fields.As a kind of waveguide, functionally graded materials can be tested by means of wave propagation characteristics.Based on this principle, a brief summary is given as follows: firstly, the series expansion iteration method is used to calculate the propagation of force waves in functionally graded materials.The propagation characteristics of stress waves in frequency domain and time domain and the influence of gradient coefficient on dispersion characteristics are discussed.Secondly, the propagation characteristics of Love waves in functionally graded materials are studied by using variational method. The dispersion relation equation of Love waves in functionally graded materials is derived, and the influence of thickness on the dispersion characteristics of Love waves is discussed with an example.The correctness of the theory is proved by comparison with the exact solution.Finally, the propagation characteristics of PSV coupling waves in functionally gradient plates are studied.The propagation characteristics of Rayleigh waves in functionally graded plates with infinite thickness and the positive and negative mode propagation characteristics of Lamb waves with finite thickness are discussed respectively.This study is helpful to the nondestructive testing of functionally graded materials, the survey of mineral resources and the prediction of seismic data, and also provides theoretical assistance for the optimization and design of functionally graded materials.
【学位授予单位】：石家庄铁道大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TB34

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