纳米Si3N4 对TC4钛合金微弧氧化层微观结构和性能的影响

在基电解液中加入氮化硅纳米颗粒，对TC4钛合金进行微弧氧化（MAO）处理，研究了Si₃N₄浓度对微弧氧化层表面形貌、耐蚀性和耐磨性的影响。添加Si₃N₄的MAO层呈现多孔结构，当Si₃N₄浓度为1 g/L时，涂层厚度最大，且经过7 d的酸腐蚀试验，该涂层的耐蚀性良好，腐蚀速率最低，约为0.057 mg·cm^-2·d^-1。随着Si₃N₄的加入，MAO涂层的抗菌性能先升高后降低。当Si₃N₄的添加量为1 g/L时，该MAO层的抗菌性能最好。Si₃N₄的加入能明显提高涂层在模拟海水中的耐磨性。当Si₃N₄的添加量为3和4 g/L时，所得涂层的摩擦系数低且稳定，且添加3 g/L Si₃N₄制备来的MAO涂层表现出优异的耐磨性。

Influence of Si3N4 Nanoparticles on Microstructure and Properties of Microarc Oxidation Coatings on TC4 Alloy

TC4 titanium alloy was treated by microarc oxidation (MAO) with Si₃N₄ nanoparticles into the base electrolyte. The effect of the Si₃N₄ content on the surface morphology, corrosion resistance, and wear resistance of the coatings was studied. The results show that MAO coatings with Si₃N₄ addition present the porous structure, and the coating is the thickest as the Si₃N₄ content is 1 g/L. The coating with the addition of 1 g/L Si₃N₄ after acid corrosion test for 7 d shows excellent corrosion resistance with the lowest corrosion rate of about 0.057 mg·cm^-2·d^-1. With the addition of Si₃N₄, the antibacterial property of MAO coatings is firstly increased and then decreased, which is optimal when the Si₃N₄ addition is 1 g/L. The Si₃N₄ addition can obviously enhance the wear resistance of the coatings in the simulated seawater. When the Si₃N₄ addition is 3 and 4 g/L, the friction coefficient of MAO coatings is low and stable. In addition, MAO coating with the addition of 3 g/L Si₃N₄ shows the excellent wear resistance.