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在ＮｉＴｉ形状记忆合金表面采用三步法制备了多层梯度钛酸铅陶瓷薄膜．第一层膜采用原位水热法制备，第二层膜以醇热法制备，第三层膜应用溶胶－凝胶法制得．Ｘ射线衍射研究确认最外层薄膜具有四方钙钛矿结构．扫描电子显微镜观察表明，薄膜总厚度约为３μｍ；由里及外三层膜中的晶粒尺寸依次约为０．１μｍ、０．２μｍ和０．３μｍ．在陶瓷膜与记忆合金基体的界面处可观察到明显的根状结构，而且在三层陶瓷膜之间的界面处也观察到类似的结构．ＥＤＸ成分分析结果表明，多层薄膜中钛与铅的成分呈梯度变化；从膜的外层到内层，Ｐｂ／Ｔｉ比值逐渐减小
Multi-layer graded lead titanate ceramic films were prepared by three-step method on the surface of NiTi shape memory alloy. The first layer was prepared by in situ hydrothermal method. The second layer was prepared by alcohol thermal method. The third layer was prepared by sol-gel method. X-ray diffraction studies confirmed that the outermost film has a tetragonal perovskite structure. Scanning electron microscopy showed that the total thickness of the film was about 3μm; the grain sizes in the inner and outer three-layer films were about 0.1μm, 0.2μm and 0.3μm, respectively. A clear root-like structure was observed at the interface between the ceramic film and the memory alloy substrate, and a similar structure was also observed at the interface between the three ceramic films. The results of EDX analysis show that the composition of titanium and lead in the multi-layer thin film changes with gradient. From the outside to the inside of the film, the Pb / Ti ratio gradually decreases