Ti6A14V合金等离子体基氧离子注入层的层状结构

Layered structure of oxygen-implanted layer on Ti6Al4V alloy by plasma based ion implantation

采用等离子体基氧离子注入技术对Ti6A14V合金进行表面改性。注入负脉冲电压分别为10、20、30、40、50kV,注入剂量为0.6×10^(17)ions/cm^2。用XPS分析了注氧层中元素的分布和化学态。结果显示,注入电压增加,氧的浓度深度分布增加。注入氧元素的浓度深度分布曲线不同于束线式注入氧元素的类高斯分布,表面氧浓度最大,随着深度的增加出现一个略倾斜的氧浓度平台,该平台的宽度随注入电压增加而增加。氧离子注入引起基体元素Ti、Al、V的浓深分布发生变化,近表面区域Ti的原子百分含量减少,Al的含量增高,而V未检测到。并且随着注入电压的增加,近表面区域富集Al的浓度明显增加,富Al贫V的区域也明显加大。注入样品的改性层具有相似的层状结构,由表及里依次为表面污染层、TiO_2和Al_2O_3组成薄的外层、内层在改性层中占的比例最大,由TiO_2、Ti_2O_3、TiO、Ti、Al、Al_2O_3、V和VO组成。

The surface modified layer on Ti6Al4V alloy by oxygen plasma based ion implantation （O-PBII） at pulsed voltages ranging from -- 10 kV to --50 kV was studied by X-ray photoelectron spectroscopy （XPS）. The results show that the thickness of oxide layer increases with the implanting voltage. The oxygen profile in the implanted sample is different from Gaussion-like distribution in the sample treated by beam-line ion implantation of oxygen. The oxygen concentration has a maximum value at surface, and then an oxygen concentration plateau appears along the depth direction, and moreover, the plateau broadens with implanting voltage. Oxygen implantation brings a variation of distribution of substrate elements such as Ti, Al and V. In the outmost portion of the modified layer, the titanium content decreases, aluminum enriches, and no vanadium is detected. Furthermore, the high implantation voltage strengthens the phenomenon of Al enrichment and V deficiency. All implanted samples have a modified layer with the similar layered structure, where a contamination layer exists at the top surface followed by a thin layer of TiO2 plus Al2O3, and then the inner layer is predominant in the modified layer and it consists of TiO2, Ti2O3, TiO, Ti, Al, Al2O3, V and VO.