Titanium alloy plasma polishing process and its performance analysis

This study systematically investigated the electrolytic plasma polishing (PEP) process using TC4 titanium alloy as the subject material, aiming to address issues related to surface uniformity, residual stress, and wettability inherent in traditional mechanical polishing (MP) and chemical polishing (CP). Orthogonal and Box-Behnken experimental designs revealed four distinct stages of anodic discharge during PEP. The coupling mechanism between oxide film formation and stripping was elucidated, and key process parameters (voltage, temperature, time) were optimized. Optimal PEP conditions were determined as: temperature 85°C, duration 6 min, voltage 280 V, yielding a high-precision surface with Ra = 0.063 μm. Results demonstrate that PEP-treated titanium alloy surfaces exhibit micro-level flatness and excellent uniformity, with elemental composition consistent with the master pattern (MP) and no new phase formation. The treated surfaces display outstanding tensile strength and significantly reduced residual stress, along with favorable wettability. In simulated high-humidity environment testing, they demonstrate excellent corrosion resistance.