A micromechanical model for phase-change composites

Phase-change composites have a wide range of tunable mechanical properties caused by temperature-driven phase transition, and have been widely applied in many cutting-edge fields like soft robotics. Previous studies on the effective mechanical properties of phase-change composites mostly use experimental methods, and there have been few theoretical approaches. In this work, we develop a micromechanical framework capable of tracking the effective mechanical properties of phase-change composites throughout the entire phase transition. The phase-change materials embedded in the composites are modelled as inclusions, and the non-phase-change materials are modelled as the matrix. This allows us to determine the effective mechanical properties of phase-change composites via the energy equivalency approach. Moreover, since the new phase will be generated inside the phase-change inclusions in the form of sub-inclusions during the phase transition, the inclusions are modelled as two-phase composites, and their effective mechanical properties are then determined using the Mori-Tanaka method. Finally, by comparing theoretical predictions with experimental data, the accuracy and reliability of the present model are verified. We believe that the proposed model can serve as a powerful tool for evaluating the effective mechanical properties of phase-change composites and provide theoretical guidelines for the design of advanced devices with tunable mechanical performance.

Automated summary

In this study, a micromechanical framework is developed to track the effective mechanical properties of phase-change composites throughout the phase transition, and its accuracy and reliability are verified. The proposed model can provide theoretical guidelines for the design of advanced devices with tunable mechanical performance.