Ceramic coatings on niobium substrates are fabricated by hot-pressing the niobium with cast iron at 1100 °C. The interstitial carbon atoms diffuse into the niobium, and NbC and Nb₂C precipitate in the surface, forming a ceramic coating. The total volume fraction of the ceramic phases in the coating reaches 92%, and the grain size is in the range of 170–1000 nm. Both the volume fraction and the grain size of the ceramic phases decrease with increasing depth with respect to the coating surface, displaying a gradient microstructure. In the coating, the crystallographic orientations of NbC and Nb₂C are randomly distributed. In the substrate, some isolated NbC and Nb₂C nuclei exhibit the Kurdjumov–Sachs orientation relationship and the Porter orientation relationship with the matrix respectively, namely $\left[1\overline{1}1\right]\left(10\overline{1}\right)$_NbC//$\left[1\overline{1}0\right]\left(11\overline{1}\right)$_Nb and $\left[10\overline{1}0\right]\left(0001\right)$_Nb2C//$\left[110\right]\left(1\overline{1}5\right)$_Nb. The coating remarkably improves the surface hardness of the niobium from 110 HV to 1600 HV, and it is strongly bonded with the substrate.

铌基材上的陶瓷涂层是通过用铸铁在1100°C下热压铌来制造的。间隙碳原子扩散到铌中，并且NbC和Nb ₂ C在表面沉淀，形成陶瓷涂层。涂层中陶瓷相的总体积分数达到92％，晶粒尺寸在170-1000 nm范围内。相对于涂层表面，陶瓷相的体积分数和晶粒尺寸都随着深度的增加而减小，表现出梯度的微观结构。在该涂层中，NbC和Nb ₂ C的晶体学取向是随机分布的。在衬底中，一些隔离的NbC和Nb ₂C核分别表现出与矩阵的Kurdjumov–Sachs取向关系和Porter取向关系，即 $\left[\mathrm{1个}\overline{\mathrm{1个}}\mathrm{1个}\right]\left(10\overline{\mathrm{1个}}\right)$_NbC //$\left[\mathrm{1个}\overline{\mathrm{1个}}0\right]\left(11\overline{\mathrm{1个}}\right)$_铌和$\left[10\overline{\mathrm{1个}}0\right]\left(0001\right)$_Nb2C //$\left[110\right]\left(\mathrm{1个}\overline{\mathrm{1个}}5\right)$_铌。该涂层将铌的表面硬度从110 HV显着提高到1600 HV，并且与基材牢固结合。