(1. 湖北理工学院 机电工程学院，黄石 435003；
2. 华中科技大学 材料成形与模具技术国家重点实验，武汉 430074)
摘 要: 对Ti(C,N)基金属陶瓷基体上沉积的TiAlCrN涂层在800~1 000 ℃静态空气中的氧化行为进行研究，并与在相同实验条件下的TiAlN涂层以及Ti(C,N)基金属陶瓷基体的氧化行为进行比较。采用分析天平、XRD和SEM (EDS)等分析测试手段对涂层和金属陶瓷基体的高温氧化质量增加特性、氧化产物的物相以及氧化膜的表面和截面形貌进行了研究。结果表明：TiAlCrN涂层在800、900和1 000 ℃的静态空气中氧化质量增加速率最小，氧化膜的表面颗粒也最细小；TiAlCrN涂层在1 000 ℃的氧化产物为TiO2、Al2O3以及少量非计量化合物Cr2O2.4；TiAlCrN涂层在1 000 ℃氧化4 h形成的氧化膜内部有一富含Al2O3和Cr氧化物的氧化层，富Al、Cr内层对氧离子向涂层内部扩散具有强烈的阻碍作用；Cr元素提高涂层中贫Al区的抗氧化性能以及与Al2O3形成(Al, Cr)2O3阻止氧向内扩散，使得TiAlN涂层添加Cr后高温抗氧化能力得到提高。
关键字: TiAlCrN涂层；氧化行为；氧化膜；扩散
（1. School of Mechanic and Electric Engineering, Hubei Polytechnic University, Huangshi 435003, China;
2. State Key Laboratory of Material Processing and Die and Mould Technology,
Huazhong University of Science and Technology, Wuhan 430074, China）
Abstract:The oxidation behaviour of TiAlCrN coating deposited on Ti(C,N)-based cermet was investigated in static air at 800-1 000 ℃. The oxidation behaviours of TiAlN coating and Ti(C,N)-based cermet substrate also were compared under the same condition. The analytical balance, XRD and SEM(EDS) were employed to observe high temperature oxidation mass gains, oxide phase identification and oxide film morphology of coatings and substrate. The results show that the mass gains rate of TiAlCrN coating is the lowest in 800, 900 and 1 000 ℃ static air among these samples. The oxidation products at 1 000 ℃ are TiO2, Al2O3 and a little of non-stoichiometric compound Cr2O2.4. There is a Al2O3-rich and Cr-rich oxide layer in the TiAlCrN coating oxide film, and this oxide layer hinders the diffusion of oxygen ions to the inner. Cr improves the oxidation resistance of Al-poor areas in TiAlCrN coating and reacts with Al2O3 to form (Al, Cr)2O3, thereby, the oxidation resistance of TiAlN coating is improved after Cr is added.
Key words: TiAlCrN coating; oxidation behaviour; oxide film; diffusion
