含空心球涂层粒子复合材料界面的脱粘应力分析

ANALYSIS OF DEBONDING STRESS IN SYNTACTIC FOAMS WITH COATED HOLLOW SPHERICAL INCLUSIONS

在球对称拉伸载荷作用下针对空心球涂层复合材料分析了空心球涂层粒子增强复合材料的局部应力场,得到了界面临界脱粘应力的解析表达式.讨论了各相几何参数对非均匀涂层空心球粒子临界脱粘应力的影响,比较了均匀涂层和非均匀涂层的脱粘应力.结果表明:在球对称拉伸下界面脱粘更容易发生在涂层相与基体相界面间,空心球的壁厚和涂层厚度是影响界面临界脱粘应力的重要因素,因而选择适当的空心球、涂层厚度和提高界面粘结能将有利于提高界面的临界脱粘应力.

The stress field in syntactic foams with coated hollow spherical inclusions is calculated under hydrostatic tension. Formulae of the critical stresses for interfacial debonding are derived by the energy criterion. Consequently, the influences of geometrical parameters of each phase on the critical stresses for interfacial debonding are discussed for inhomogeneous interphase, and differences between inhomogeneous and homogeneous interphase are obtained. It indicates that interfacial debonding will take place at first at the interphase between coating and matrix. The thickness of hollow sphere and the coating thickness are the important factors to affect the critical debonding stress of interphase. Therefore, the critical stress for interfacial debonding could be enhanced by selecting the proper hollow sphere, coating thickness and by increasing the interfacial adhesive energy.