Study on the tribological properties of Si₃N₄/polyamide-imide composites

Abstract

Si3N4 whiskers were modified with triethoxysilane as a means to improve the interfacial interaction with a poly-amide imide (PAI). The Si3N4/PAI composites were prepared by in-situ polymerization as an approach to improve the friction behavior and mechanical properties in order to meet the performance needs of electrical transformers and motors in harsh environments. 4,4′-diamino diphenyl ether, m-phenylenediamine, triethylamine, trimellitic anhydride chloride, and Si3N4 whiskers were used to manufacture Si3N4/PAI composite, which was then characterized for friction and mechanical behavior. The research showed that the addition of Si3N4 whiskers improved the mechanical properties and friction properties of PAI. When the whisker content was 10 wt%, the tensile strength of the composite was 137.5 MPa, which is 15% higher than pure PAI, and the wear rate was 0.69 × 10-8 g/N·m, which is 57% lower than pure PAI, and the friction coefficient was 0.47, which was an increase of 9%. In aerospace, machinery, and transportation applications, these materials may have better performance due to their improved combination of properties.