论文部分内容阅读
功能梯度材料具有复杂的细部结构,其内部构造远比匀质材料复杂,因此其构件动力分析很难求得其解析解。该文建议一种新颖的功能梯度构件动力分析的细观元法。细观力学研究的目的在于建立材料的宏观性能同其组分材料性能及细观结构之间的定量关系,它可揭示不同的材料组合具有不同的宏观性能的内在机制。此法可实现材料细观结构到构件宏观响应的直接过渡分析,而计算单元与自由度又等同一般常规有限元,却使得组成功能梯度材料构件的各种材料细观构造得到反映。通过细观元技术,对具有中等组分不同网状结构功能梯度构件进行三维动力特性分析,并给出其三维固有频率及振型的三维分布,特别是给出了不同网格结构功能梯度板件应力振型的平面等值线图差异。结果表明:不同细观网格结构对功能梯度材料结构三维动力响应有较明显影响。
Functionally graded materials have complex details and their internal structure is much more complicated than homogeneous materials. Therefore, it is very difficult to obtain the analytic solution for the structural dynamic analysis of FGM. This paper proposes a novel meso-element method for dynamic analysis of functionally graded components. The purpose of meso-mechanics research is to establish the quantitative relationship between the macroscopic properties of materials and the properties of their component materials and mesostructure, which can reveal the intrinsic mechanism of different macroscopic properties of different material combinations. This method can realize the direct transition analysis of the material mesostructure to the component macroscopic response, but the calculation unit and the degree of freedom are the same as the conventional general finite element, but the fine structures of various materials that make up the functionally graded material component are reflected. Through the meso-element technology, the three-dimensional dynamic characteristics of functionally graded members with different reticular structures with medium composition were analyzed and the three-dimensional distributions of three-dimensional natural frequencies and mode shapes were given. In particular, Difference of planar contour map of stress mode. The results show that different mesoscopic grid structures have obvious influence on the three-dimensional dynamic response of FGM.