Silane treatment of Fe ₃ O ₄ and its effect on the magnetic and wear properties of Fe ₃ O ₄ /epoxy nanocomposites

In this study, the effect of silane treatment of Fe ₃ O ₄ on the magnetic and wear properties of Fe ₃ O ₄ /epoxy nanocomposites was investigated. Fe ₃ O ₄ nanopowders were prepared by coprecipitation of iron(II) chloride tetrahydrate with iron(III) chloride hexahydrate, and the surfaces of Fe ₃ O ₄ were modified with 3-aminopropyltriethoxysilane. The magnetic properties of the powders were measured on unmodified and surface-modified Fe ₃ O ₄ /epoxy nanocomposites using SQUID magnetometer. Wear tests were performed on unmodified and surface-modified Fe ₃ O ₄ /epoxy nanocomposites under the same conditions (sliding speed: 0.18 m/s, load: 20 N). The results showed that the saturation magnetization (M _s ) of surface-modified Fe ₃ O ₄ /epoxy nanocomposites was approximately 110% greater than that of unmodified Fe ₃ O ₄ /epoxy nanocomposites. This showed that the specific wear rate of surface-modified Fe ₃ O ₄ /epoxy nanocomposites was lower than that of unmodified Fe ₃ O ₄ /epoxy nanocomposites. The decrease in wear rate and the increase in magnetic properties of surface-modified Fe ₃ O ₄ /epoxy nanocomposites occurred due to the improved dispersion of Fe ₃ O ₄ into the epoxy matrix.