Texture analyses of chemically vapor deposited coatings in the Ti-C-N system by wide film Debye-Scherrer X-ray diffraction technique

Abstract
Texture analyses were performed on the chemically vapor deposited monolithic TiN, TiC, TiC_xN_y coatings and graded TiN/TiC coatings by wide film Debye-Scherrer X-ray diffraction technique. The preferred orientations of the coatings were investigated as a function of coating thickness and input gas composition. The growth of TiN and TiC coatings was initiated as randomly oriented crystallites which subsequently grew into large columnar grains with a <110> preferred orientation. The textures of TiC coatings with the same thickness changed from the <110> orientation to the <100> orientation with decreasing hydrogen concentration in the gas phase. TiC_xN_y coatings exhibited a preferred orientation of <111> up to the CH₄/CH₄+N₂ ratio of 0.14 above which a strong <100> texture developed. The texture analyses on the graded TiN/TiC coatings showed that the TiC top layers were oriented in a <100> direction perpendicular to the sample surface.