低温去合金化处理对医用镍钛合金表面性质的影响  

Effects of Dealloying Treatment at Low Temperature on the Surface Properties of NiTi Alloys

作　　者：苏向东[1] 王天民[1] 郝维昌[1] 韩峰[2] 黄亚励[3] 何力[2] 

机构地区：[1]北京航空航天大学,北京100083 [2]贵州科学院,贵州贵阳550002 [3]贵阳医学院,贵州贵阳550004

出　　处：《稀有金属材料与工程》2008年第5期859-863,共5页Rare Metal Materials and Engineering

基　　金：“贵州省优秀科技教育人才省长专项基金”资助(2005214)

摘　　要：分析了近等原子比NiTi形状记忆合金实现去合金化的热力学条件,并采用低温去合金化处理法对其进行表面改性;经SEM、XRD、XPS、EDX,模拟体液(SBF)仿生沉积等分析研究表明,NiTi合金经去合金化处理后,在合金表面选择性地除去了有害元素镍,在距表层约130nm深度内原位制备出完全无镍的具有纳米结构的二氧化钛层;同时结合上羟基(OH-),在SBF溶液中,经低温去合金化处理后的合金表面具有诱导Ca/P沉积的能力,从而提高了NiTi形状记忆合金的生物相容性。After calculated the dealloying conditions of thermodynamics, a dealloying treatment method is applied to nearly equiatomic NiTi alloy so as to remove the harmful element from NiTi alloys and form a Ni-free titanium oxide layer on the surface. The surface of sample is analyzed by SEM, XRD, XPS and EDX, and then immersed in SBF solution for up to 14 days in order to observe the Ca/P deposition. The results show that the dealloying treatment at low temperature leads to a Ni-free surface layer with a nanometer structure at the depth of 130 nm, and in situ to form a titania surface with a degree of bioactivity and ability to induce Ca/P precipitates combined with hydroxyl （OH^-） groups in the solution simultaneously. As a consequence, the dealloying treatment can increase the biocompatibility of NiTi shape memory alloys for medical applications.

关 键 词：NITI合金 去合金化 表面改性 热力学条件 纳米二氧化钛 

分 类 号：TG146.15[一般工业技术—材料科学与工程] R318.08[金属学及工艺—金属材料]