Hydrothermal Surface Modification of a Low Modulus Ti-Nb Based Alloy

摘要:

采用尿素溶液对一种低模量近b型钛合金（Ti-25Nb-3Zr-2Sn-3Mo, 或 TLM合金）进行不同温度的水热处理。采用SEM、XRD、XPS、压入法和接触角测试分析了TLM合金处理后的表面结构、化学成分、附着性和亲水性。在105和120 ℃水热处理后，合金表面形成了钛酸铵的纳米片薄膜；而150 ℃水热处理后形成了纳米颗粒薄膜，由锐钛矿TiO2和Nb2O5组成。随后的400 ℃退火热处理使铵盐分解和二氧化钛结晶。生成的氧化物薄膜具有良好的附着性。复合处理增强了TLM合金的亲水性，这有利于改善其生物相容性。

Abstract:

A low modulus near b type titanium alloy (Ti-25Nb-3Zr-2Sn-3Mo, or TLM alloy) was subjected to hydrothermal treatments with a urea solution at different temperatures followed by heat treatment. The surface structure, the chemical composition, adhesion and hydrophilicity of the treated TLM alloy were investigated by SEM, XRD, XPS, Rockwell-C indentation test and contact angle measurement. The results show that nanosheet films of ammonium titanate can be formed at 105 and 120 °C, while the nanoparticle film of anatase TiO2 containing Nb2O5 is formed at 150 °C on the alloy surface. The subsequent annealing heat treatment at 400 °C can decompose the ammonium salts and crystallize titania. The obtained oxide films have a good adhesion. The duplex treatment has enhanced the hydrophilicity of the TLM alloy, and it would be good for its biocompatibility.