Fabrication and anti-corrosion performance of superhydrophobic silane film on sintered NdFeB

An eco-friendly superhydrophobic protective film (DTMS/TEOS silane film) was fabricated on sintered NdFeB substrate through the utilization of electrochemically assisted deposition technology. The structure, properties, and film-forming mechanism of dodecyltrime-thoxysilane (DTMS)/tetraethoxysilane (TEOS) silane films were comprehensively analyzed using Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), potentiodynamic polarization curves and electrochemical impedance spectroscopy (EIS). Based on the test results, it can be determined that this film has a superhydrophobic property with a hydrophobicity angle of 152 degrees. This special property can be attributed to the long alkyl chains in the DTMS molecule, the rough morphology, and the low surface energy of the DTMS/TEOS silane film. The surface of sintered NdFeB is coated with a layered three-dimensional network silane film that forms through the condensation of silanol substances. This film provides excellent corrosion resistance to the sintered NdFeB substrate, reducing its corrosion current density to 2.02x10-6 A/cm2. Moreover, the impact of film on the magnetic characteristics of sintered NdFeB was assessed and found to be minimal.