碱热处理对Ti-3Cu合金表面特征及抗菌性能的影响

Effect of Alkali Heat Treatment on Surface Characteristicsand Antibacterial Properties of Ti-3Cu Alloy

摘要:

Ti-3Cu表现出良好的力学性能、耐蚀性能及优异的抗菌性能。碱热处理是一种有效的钛合金表面处理方法,它可以提高钛合金的表面生物相容性。本文研究了碱热处理对抗菌钛合金显微组织、表面粗糙度、接触角及抗菌性的影响规律,探讨了碱热处理应用于Ti-3Cu表面生物改性的可能性。研究结果表明：碱热处理后在钛合金表面形成一层钛酸盐凝胶层,表面分布有大量尺寸约100 nm的纳米级微孔,这使得合金的粗糙度降低,但合金表面的亲水性提高。合金表面钛酸盐凝胶层的形成使的合金的抗菌性能由处理前的92%降低到碱热处理后的71%。细菌的粘附实验也证实碱热处理一定程度上降低了合金的抗菌性能。分析认为,表面形成的钛酸盐凝胶层部分阻断了合金中抗菌相Ti2Cu与细菌的接触,因此降低了合金的抗菌效果。

Abstract:

Ti-3Cu alloy exhibits excellent mechanical properties, corrosion resistance and antibacterial properties. Alkali heat treatment is an effective surface treatment method for titanium alloys, which can improve the surface biocompatibility of titanium alloys. The effect of alkali heat treatment on the microstructure, surface roughness, contact angle and antibacterial properties of Ti-3Cu alloy were studied in this research to reveal the possibility of applying alkali heat treatment to biological surface modification of Ti-3Cu alloy. The results have shown that a layer of titanate gel was formed on the surface of titanium alloy after alkali heat treatment, and a large number of nano-sized pores with a size of about 100 nm were distributed homogeneously on the surface of the gel layer, which reduced the roughness of Ti-3Cu alloy but improved the hydrophobicity of the alloy surface. The formation of the titanate gel layer on the alloy surface reduced the antibacterial property of the alloy from 92% before treatment to 77% after alkali heat treatment. The bacterial adhesion test also confirmed that alkali heat treatment reduced the antibacterial property of the alloy. It is believed that the titanate gel layer partly blocked the contact between Ti₂Cu phase and bacteria in the alloy, so the antibacterial effect of the alloy decreased.