Mechanical properties of cermet composites with various geometrical tortuosity of metal phase: Fractal characterization

Although the mechanical properties of cermet composites have been investigated extensively, how to quantitatively determine the relationship between the performances and the geometrical structures of the reinforcement phase is still one of the top challenging problems yet to be solved. To determine the influence of the geometrical structure of the reinforcement phase on the mechanical performances of composites, Cu₂O/Cu cermets were prepared with spherical or branch like Cu by the hot-pressing technology. Box-counting fractal dimension increasing rate with increasing filling content of reinforcement phase was first applied to quantitatively reflect the relationship between the geometrical structures of metal phase and the mechanical properties of composites. A simple model was developed by combining fractal theory and power law, in which the critical exponents were determined via experimental results. This study not only provides a pathway to understand the mechanisms of the geometrical structure of the reinforcement phase to the mechanical properties of composites, but also sheds light on the geometrical tortuosity characterization by using fractal approach in cermet composites.