复合活化处理镍钛合金及磷灰石层的仿生沉积

Biomimetic Deposition of Apatite Coating on NiTi Shape Memory Alloy after a Composite Bioactive Treatment

摘要:

利用H2O2和NaOH溶液对近等原子比NiTi记忆合金（SMA）进行复合活化处理,并采用XRD,SEM,XPS,FTIR等研究了活化处理后NiTi SMA的表面结构及其在模拟体液（SBF）中磷灰石涂层的仿生沉积过程.结果表明：复合活化处理后NiTi SMA表面为贫Ni、富含Ti-OH的蠕虫状活性层,由结晶度较低的TiO2,钛酸纳（Na2TiO3）及少量的Ni2O3组成,在SBF中表面活性层诱导磷灰石形核及生长,短期内在镍钛基体表面获得了理想的磷灰石层.

Abstract:

The surface structure was characterized by XRD, SEM, XPS and FTIR for the NiTi shape memory alloy (SMA) with a nearly-equiatomic ratio after composite bioactive treatment in H2O2 and subsequent NaOH solutions. The biomimetic deposition process of apatite coatings on the pretreated NiTi SMA was studied in the simulated body fluid (SBF). The experimental results indicate that a wormlike bioactive layer with many Ti-OH groups and a trait of Ni2O3 is formed on the NiTi substrate after the composite bioactive treatment, which was mainly composed of the poorly-crystallized Na2TiO3 and TiO2 and relatively poor in Ni. The bioactive layer can induce the apatite nucleation and growth in SBF and obtain an ideal apatite coating on NiTi substrate in a short term.