连续变化界面层对复合材料弹性性能影响

界面层对复合材料的变形和破坏有着重要的影响,实际界面层的性能是随位置而连续变化的,但目前大多数考虑界面层影响的工作都假设界面层材料性能均匀或分层均匀。假设界面层的性能是空间位置的幂函数形式,给出了具有上述界面层的纤维和球形夹杂在球压和剪切载荷下的解,然后利用平均场方法建立了上述复合材料的有效弹性性质与微结构的联系。还将上述方法与均匀界面层模型进行了比较,计算结果表明,界面层的性质对复合材料有效性质和局部应力的分布有着重要影响。 

EFFECT OF GRADUAL INTERPHASE ON ELASTIC PROPERTIES OF COMPOSITES

An interphase plays a key role in composites performance, its mechanical properties vary spatially due to diffusion and chemical reaction, but most actual models assume uniform material property in the interphase region. It is assumed that the material property of an interphase follows a power law function. The coated fiber and particle with such interphase in an infinite matrix under hydrostatic and pure shear loading have been analyzed respectively; the local stresses and the average stresses in the fiber or particle and the interphase are obtained analytically. With the help of the mean field concept in micromechanics, the effective moduli of the composite with such coated fibers or particles are derived as a function of the microstructure. The computed results show that the presence of an interphase can have an important influence on the effective property and local stress distribution of the composites.