First-Principles Calculation of the Bonding Strength of the Al₂O₃-Fe Interface Enhanced by Amorphous Na₂SiO₃

In this paper, the interfacial adhesion work (W_ad), tensile strength, and electronic states of the Fe-amorphous Na₂SiO₃-Al₂O₃ and Fe-Al₂O₃ interfaces are well-investigated, utilizing the first-principles calculations. The results indicate that the Fe-amorphous Na₂SiO₃-Al₂O₃ interface is more stable and wettable than the interface of Fe-Al₂O₃. Specifically, the interfacial adhesion work of the Fe-amorphous Na₂SiO₃ interface is 434.89 J/m², which is about forty times that of the Fe-Al₂O₃ interface, implying that the addition of amorphous Na₂SiO₃ promotes the dispersion of Al₂O₃ particle-reinforced. As anticipated, the tensile stress of the Fe-amorphous Na₂SiO₃-Al₂O₃ interface is about 46.58 GPa over the entire critical strain range, which is significantly greater than the Fe-Al₂O₃ interface control group. It could be inferred that the wear resistance of Al₂O₃ particle-reinforced is improved by adding amorphous Na₂SiO₃. To explain the electronic origin of this excellent performance, the charge density and density of states are investigated and the results indicate that the O atom in amorphous Na₂SiO₃ has a bonding action with Fe and Al; the amorphous Na₂SiO₃ acts as a sustained release. This study provides new ideas for particle-reinforced composites.