不同氮气分压下不锈钢基体氮化钛涂层的制备及性能表征

Preparation and Characterization of TiN Coatings on Stainless Steel Under Various Partial Pressure of Nitrogen

在不同氮气分压下,采用多弧离子镀技术在不锈钢基体表面制备了光滑而致密的TiN涂层,利用光学显微镜、X射线衍射仪分别观测了TiN涂层表面形貌及涂层物相,利用显微硬度仪和电化学腐蚀仪器表征了涂层的显微硬度和电化学腐蚀性能。结果表明:在总压不变的情况下氮气分压越高,TiN涂层的生成率越大,涂层显微硬度小幅增大。氮气分压1.6 Pa下制备的TiN涂层表面缺陷最少,显微硬度相比基体提高了2倍。当氮气分压从0.4 Pa逐渐增加到1.6 Pa时,腐蚀电位相应地从-0.579 V提高到-0.249 V,腐蚀电流则从3.4×10^-5 A降低到1.2×10^-5 A,涂层耐腐蚀性能显著提高。

In order to study the microstructure and properties of TiN coating under various partial pressure of nitrogen, TiN coatings was firstly prepared on the surface of stainless steel substrate by using a multi-arc ion plating process. The surface morphology and phases of the prepared TiN coating were observed by optical microscopy, X-ray diffractometer, and the microhardness and electrochemical corrosion performance of the coating were characterized by using a microhardness tester and an electrochemical corrosion testing instrument. The results show that with the total pressure being constant, a higher partial pressure of TiN can bring in high generation rate of TiN coating with a little increased microhardness. It is shown that TiN coating prepared under nitrogen partial pressure of 1.6 Pa is the best due to the fewest surface defects, and has the microhardness twice as high as that of the substrate. When the partial pressure of nitrogen increases from 0.4 Pa to 1.6 Pa, the corrosion potential increases from-0.579 V to-0.249 V and the corrosion current increases from 3.4 ×10^-5 A to 1.3 ×10^-5 A, which leads to the coating performance remarkably improved.