Micromechanical Approach to Predict Mechanical Properties of Particulate-Dispersed Composites with Dissimilar Interfacial Phases

Abstract

The mechanical properties of composites are affected by their constituents. For the development of high-performance composites, it is expected that a technique will be developed which can predict the mechanical properties of composites based on the mechanical properties of their constituents. This study developed a technique based on a micromechanical approach to predict the mechanical properties of composites with interfacial phases between reinforcements and matrix. A double-inclusion model (Hori and Nemat-Nasser, 1993) is effective for the solution of such problems, of which the validity remains unclear. Problems with a particle surrounded by an interfacial phase embedded in an infinite body were calculated via the model and finite element analysis to verify the model. It was found that the macroscopic average stress of the double inclusion could be accurately solved by the model, although the microscopic stress of each phase could not be calculated with high accuracy. Therefore, a micromechanical approach based on the model was formulated and applied to particulate-dispersed composites consisting of zirconia and titanium, and fabricated by spark plasma sintering, in which Ti oxides were created along the interface between zirconia and titanium. As a result, the elastic-plastic stress–strain curves of the composites could be predicted. The approach can investigate the mechanical properties of composites with various shapes of reinforcement surrounded by dissimilar materials in a matrix. It can be concluded that the approach is promising for the development of composites with an excellent mechanical performance.