研究了航空钛合金损伤结构梯度改性修复层和Ti600基体在800 ℃下的氧化行为; 采用恒温或循环氧化增重法、氧化速度常数、活度等理论计算研究了氧化的热力学和动力学规律; 利用扫描电镜(SEM)和X射线衍射(XRD)等分析了氧化膜形貌和组成。结果表明: 梯度修复层有较好的抗氧化性能, 其循环氧化动力学曲线基本符合抛物线规律; Ti600基体属次抗氧化级, 其循环氧化动力学曲线近似符合抛物线-直线规律; 梯度修复层氧化膜由金红石结构的TiO2和少量Cr2O3组成, 厚度5～6 μm, 与基体连接紧密, 且致密、连续, 为短纤维状组织; Ti600基体的氧化膜厚度达55 μm左右, 明显分为内氧化区、中致密层和外疏松多孔层, 为多面体规则形状组织。

The high temperature oxidation behavior of FGRL and Ti600 alloy has been investigated. Thermodynamic and dynamic laws were studied by means of calculating the oxidation weight gain, oxidation rate constants and activities. The microstructure and morphology of oxides were examined with XRD, EDS and SEM. The results show that FGRL exhibits the parabolic rule of oxidation rate at 800 ℃. Ti600 alloy belongs to secondarily inoxidizable class, and obeys the parabolic-linear rule. The main oxidation products of FGRL are TiO2 and Cr2O3. The morphology possesses densely fine fibrous crystal, 5-6 μm thickness. Otherwisely, that is regularly polygonal crystal, 55 μm thickness and obviously composed of internal oxidation, middle stratum compactum and external tectorium, to Ti600.