Ti/TiAl微层板的高温氧化机理研究

对前期采用电子束物理气相沉积法制备的Ti/TiAl微层板进行了高温氧化研究，利用XRD、SEM、EDS对涂层的相结构变化、表面形貌、化学成分进行了实验分析。结果表明，随着温度升高，Al向富Ti区域的扩散越来越快，界面融混现象愈加严重。微层板的高温氧化机制为：Ti原子的不断外扩散使氧化膜中各层的Ti含量都有增加，Al2O3和TiO2分别具有热力学生成优势和动力学生长优势，表面氧化由最初的Al2O3膜逐渐向(TiO2 Al2O3)及TiO2过渡。

Study on Oxidation Mechanism of Ti/TiAl Micro-laminates at High Temperature

Oxidation at high temperature of Ti/TiAl microlaminates prepared by electron beam physical vapor deposition technology was studied in this paper, and then the alteration of phase structure was analyzed by X-ray Diffraction (XRD), the surface topography and composition were observed by Scanning Electron Microscopy (SEM) and Energy Dispersive Scanning(EDS). The results show that with temperature increases, diffusion velocity of Al element into Ti zone develops more and more quickly, and blending phenomenon gets more obviously. The oxidation mechanisms of Ti/TiAl microlaminated sheet at high temperature is that the Ti contents in each component layer increase gradually with the constant diffusion of Ti atoms towards surface. Al2O3 and TiO2 has the advantage of thermodynamics and dynamics growth respectively. The combined action of the two aspects lets the Al2O3 oxide film change to the (TiO2 Al2O3)and TiO2 oxide film gradually.