Study on magnetic field-electrochemical composite polishing mechanism of TC4 titanium alloy

Abstract To improve the high-quality polishing efficiency of TC4 titanium alloy structures, a novel magnetic field-assisted electrochemical composite polishing method was developed. The surface topography, surface roughness, material removal rate, corrosion resistance, mechanical properties, and wettability of TC4 titanium alloy were characterized both before and after the polishing process. The results show that the optimum combination of experimental parameters after the introduction of magnetic field is: magnetic field angle is 90°, magnetic field strength is 0.4 T, polishing time is 6 min, the surface roughness Ra of the workpiece after magnetic field-electrochemical composite polishing is reduced from 256 nm to 19 nm, the roughness reduction rate is 92.6%, the material removal rate is 3.695 μm min −1 , and the polished surface achieves a mirror effect. The self-corrosion potential of the polished surface increased from −0.448 V to −0.427 V and the self-corrosion current density decreased from 2.979 × 10 −7 A·cm −2 to 7.872 × 10 −8 A·cm −2 . The magnetic field-enhanced electrochemical composite polishing process yields surfaces with improved hardness uniformity and enhanced hydrophobic characteristics, while achieving a 40% increase in polishing efficiency. These performance metrics demonstrate that this advanced polishing technique meets the stringent requirements for high-quality, high-efficiency processing of medical-grade alloys, positioning it as a promising technology for precision surface finishing applications in the biomedical field.