A niobium-modified layer on pure titanium surface was obtained by means of double glow plasma surface alloying technique. The modified layer was uniform, continuous, compact and well adhered to the substrate. The niobium composition in the modified layer decreased gradually from the surface to the substrate. The oxidation behavior of the niobium-modified layer was investigated and compared with the untreated surface at 900 °C for 100 h. Characterization of the layers was performed using X-ray diffraction and scanning electron microscope, respectively. The test results show that the oxidation behavior of pure titanium was improved by niobium alloying process. Niobium has a positive influence on the oxidation resistance.
Wang, W. B., Zhong, X., He, Z. Y., Wang, Z. X., & Zhang, P. Z. (2007). Plasma niobium surface alloying of pure titanium and its oxidation at 900 °C. Chinese Journal of Aeronautics, 20(2), 111–114. https://doi.org/10.1016/S1000-9361(07)60015-6