为了获得采用EB-PVD技术制备Ti-Al薄板的合理工艺参数,分析了Ti-Al薄板在实际试验条件下的蒸发与沉积过程.采用相关热学理论,结合分析试验的方法并依照EB-PVD工艺特点,对蒸气粒子的传输、饱和蒸气压对蒸发原子的影响以及Al的再蒸发进行了研究.结果表明:EB-PVD工艺制备Ti-Al薄板的最佳靶基距为280mm;饱和蒸气压的差异使得材料截面呈现分层特征;加入Nb片可以减小由于Ti、Al的蒸发速率差异导致的沉积材料与靶材之间的成分偏差,Al在基板上的2次蒸发可忽略不计.工艺参数的合理设计及在熔池中添加Nb金属,能够提高Ti-Al薄板的沉积速率,并降低由于元素饱和蒸气压的差别对成分偏析的影响.
The evaporation and deposition process of Ti-Al thin sheet under actual experiment conditions was analyzed to obtain proper processing parameters of Ti-Al thin sheet prepared by EB-PVD technology.By using thermotics theory with experimental analysis and according to the trait of EB-PVD technology,the transfer of evaporating particles,the effect of saturated vapor pressure on different atoms and the re-evaporation of Al were studied.The results indicate that the optimal source-substrate distance is about 280 mm,and the cross section of deposit presents natural lamination due to the deviation of saturated vapor pressure between Ti and Al element.The addition of Nb tablet on target can reduce component deviation between deposit and target resulted from the diversity of evaporating rate of component.Besides,the effect on deposit by re-evaporation of Al can be neglected.The depositing rate can be increased and the effect of deviation of saturated vapor pressure on the component deviation can be reduced by the proper design for processing parameters and the introduction of Nb into molten pool.