多孔TiNi合金表面沉积羟基磷灰石与表征

Calcium phosphate deposition on the surface of porous TiNi alloys with different sintering temperatures in simulated body fluid

摘要:

摘 要: 采用粉末冶金方法，以Ti、Ni纯元素粉末制备近等原子比TiNi合金，并通过仿生溶液生长法对合金进行表面改性。利用X射线衍射仪（XRD）、扫描电子显微镜（SEM）和X射线能谱仪（EDS）分析不同烧结温度（950℃、1000℃、1050℃、1100℃）、不同孔隙特性的金属基体表面羟基磷灰石相组成和微观结构。实验结果表明，采用粉末冶金方法制备的TiNi合金孔隙度较高，仿生矿化后的XRD图谱中羟基磷灰石相的衍射峰尖锐。在同等时间、同等矿化条件下，羟基磷灰石在1050℃和1100℃烧结而成的多孔TiNi合金表面结晶度较高，沉积层较厚，沉积效果相对较好。在一定范围内，孔隙率的增加有利于羟基磷灰石的形核与生长；而尺寸较小的孔洞底部会形成一个低离子浓度区域，不利于磷灰石的形核与长大。

Abstract:

Near-Equiatomic TiNi alloys were successfully produced by powder metallurgy (P/M) method using Ti and Ni powders in different temperatures(950℃，1000℃，1050℃，1100℃).To obtain a material surface having excellent affinity to bone, hydroxyapatite coatings were conducted in a simulated body fluid (SBF). Phase composition and surface structure of Ca-P coatings were characterized by X-ray diffractometry (XRD), Scanning electron microscopy (SEM) and Energy dispersive X-ray spectroscopy (EDS) attached to SEM. Results indicated that porosity of TiNi alloys produced by P/M method is high and peaks of hydroxyapatite is sharp. In the same experimental condition, more apatite coatings formed on TiNi samples sintered at 1050℃ and 1100℃ due to their high porosity and pure TiNi phase that is beneficial to heterogeneous nucleation.