Analysis of a functionally graded particulate composite under flexural loading conditions

The conventional microstructures of functionally graded particulate composites are based on creating a gradient of either the particle volume fraction or the size along one dimension of the material. However, premature cracking and poor dimensional stability of such composites limit their applications. Hollow particle filled composites, called syntactic foams, present an opportunity to fabricate functionally gradient composites based on a new approach, which relies on creating a gradient of particles as per their wall thickness. The present study is focused on characterizing the functionally graded syntactic foams (FGSFs) based on this kind of structure for flexural properties. In previous studies the FGSFs based on wall thickness variation are found to have considerably higher energy absorption under compressive loading conditions compared to the FGSFs based on volume fraction variation. In this study the experimental results of flexural testing are compared with the theoretical and finite element analysis for both types of FGSFs. Results show that the flexural properties of FGSFs based on wall thickness approach can be controlled more effectively.