阴极微弧电沉积表面处理钛的高温氧化行为(英文)

High temperature oxidation behavior of titanium coated by cathodic microarc electrodeposition

在0.4mol/lAl(NO3)3乙醇溶液中,采用阴极微弧电沉积方法在纯钛表面制备出80μm厚的氧化铝涂层。研究了钛及其镀膜样品在973K的高温氧化行为,并分析了它们恒温氧化后的组织、成分和相组成。结果表明,具有氧化铝涂层的钛在973K的氧化速率降低了4倍,恒温氧化后涂层的形貌和相组成几乎保持不变。涂层/钛界面附近的较薄氧化铝致密层对抑制氧和钛原子的扩散起重要作用。阴极微弧电沉积是提高钛抗氧化性能的有效方法之一。

Cathodic microarc electrodeposition is a new method to produce oxide coatings on conductive materials.In this paper,an alumina coating up to 80 μm was fabricated on pure titanium by cathodic microarc electrodeposition technique in 0.4 mol /l Al（NO3）3 ethanol solution.The oxidation behavior of titanium and coated titanium were evaluated by isothermal oxidation at 973 K in air.Their microstructure,composition and phase constituents after oxidation test for 100 h were analyzed by means of scanning electron microscopy（SEM） and X-Ray diffraction（XRD）.It is found that the oxidation rate of the coated titanium reduces about 4 times compared with that of pure titanium at 973 K isothermal oxidation.After oxidation test,the phase constituents of alumina coating hardly change,in which the coating consists of γ-Al2 O3 and little α-Al2 O3 phases.A thin dense alumina layer close to the coating /titanium substrate plays a key role on suppressing O and Ti diffusion during the isothermal oxidation.The cathodic microarc electrodeposition is an effective method to improve the oxidation resistance of titanium.