Microstructure and texture of electrodeposited Ni-ZrC composite coatings investigated by Rietveld XRD line profile analysis

Rietveld X-ray diffraction (XRD) line profile analysis method was used to investigate the influence of applied current density on the microstructure and texture of the electrodeposited Ni-ZrC composite coatings. Crystallite size, microstrain, distribution of crystallite size, dislocation density, crystalline preferred orientation (texture), and ZrC particles content of the Ni-ZrC coatings were obtained from the Rietveld XRD line profile analysis. The results show that the crystallite size of Ni-ZrC coating increases, the microstrain and dislocation density decrease with the increasing of the current density. And the distribution of crystallite size is less uniform at higher current density. The pole figures simulated by Rietveld analysis software are coincident with the measured pole figures of Ni-ZrC coatings. The calculated relative texture coefficient (RTC) values, the simulated and measured pole figures of the coatings all illustrate that the texture of Ni-ZrC coating is modified from weak (2 2 0) to strong (2 0 0) texture with the increasing of applied current density. The microstructure evolution of Ni-ZrC composites is ascribed to the change of applied current density and ZrC content in the coatings.