酸洗预处理对Ti-6Al-4V合金微观形貌与耐腐蚀性能的影响OA

Objective To evaluate the changes in the microstructure and corrosion resistance of Ti-6Al-4V alloy after different acid pickling pretreatments and to determine the optimal pickling method for titanium alloys used as implantable biomaterials.Methods The microstructure,hydrophilic properties,and corrosion resistance of machined Ti-6Al-4V alloy samples pickled with HF+H2SO4,HF+HNO3,and HF solutions were analyzed using contact angle measurements,scanning electron microscopy(SEM),energy-dispersive X-ray spectroscopy(EDS),and electrochemical tests.Results 1.Pickling rates varied among the three solutions:HF+H2SO4(0.088 μm/s),HF+HNO3(0.064 μm/s),and HF(0.097 μm/s).2.All groups exhibited characteristic α+β phase microstructures,with a higher proportion of β phase observed in the HF+HNO3 and HF groups compared to the HF+H2SO4 group.The HF group also displayed hydride phases.Optical microscopy revealed the least pitting corrosion in the HF+HNO3 group.3.Corrosion resistance testing in simulated body fluids showed the following order of self-corrosion potential:control group>HF+HNO3 group>HF+H2SO4 group>HF group.Conclusion HF+HNO3 pickling produced Ti-6Al-4V alloy samples with smooth surfaces,a contact angle of 47.63°±2.40°,a weight loss rate of 1.11%±0.08%,and uniform removal of organic impurities and oxide films.The C/Ti and O/Ti ratios were reduced to 0.047±0.001 and 0.040±0.008,respectively.This treatment achieved higher corrosion resistance,with a self-corrosion potential of-0.676V.HF+HNO3 is recommended as the preferred pickling solution for producing implantable Ti-6Al-4V alloys with superior corrosion resistance and a clean,uniform surface.