Study on the tribological properties of complex additive of oleic acid-modified Fe₃O₄ nano-particle and PA66 powder

Fe₃O₄ nanoparticles of average diameter 8 nm, which were surface-modified with oleic acid, were prepared by chemical co-deposition method, and the tribological properties of the prepared nanoparticles and PA66 powder as additive in 32 machine oil were investigated on M-200 tribotest. Results indicate the oils adding oleic acid-modified Fe₃O₄ nanoparticles and PA66 powder exhibit good tribological properties. Under the condition of keeping friction coefficient basically changeless, and wear-scar width reduced 28% maximally. So the synergistic effect of nano-Fe₃O₄ particles and PA66 powder as lubricating additive was found.