Growth Kinetics of CrC Coating Layers on AISI D3 Obtained by Thermo-Reactive Diffusion Technique

Abstract

In this study, the characterization and growth kinetics of chromium carbide layer coated on AISI D3 cold-work tool steel by pack method thermo-reactive diffusion process in solid medium were carried out. Coatings were performed by using ferrochromium powder as Cr source at 950, 1000, 1050 and 1100 degrees C for 2 and 4 h. The carbide layers were evaluated based on microstructure, thickness, hardness, energy dispersive X-ray facility and X-ray diffraction analysis. Chromium carbide layer thickness on the coated specimens has been in the 4.2-17 mu m range depending on treatment time and temperature. Growth kinetics of the carbide layers were analyzed by measuring the depth of carbide layer as a function of temperature and time. The activation energy was estimated to be 180.13 kJ/mol. The microhardness values of the coating layers are range of 1200-1600 HV. Ball rotating micro-abrasion technique was used to carry out wear tests on the thin coating layers.