Key Engineering Materials

Thermo-reactive diffusion (N and V) on AISI 1020 steel has been obtained by an initial gas nitriding followed by vanadizing. Vanadizing was performed by pack method in the powder mixture consisting of ferro-vanadium, ammonium chloride and alumina at the temperatures of 800, 900 and 1000 degreesC for 1-4 hours. The properties of the diffusion layers, namely microstructure and phase composition, have been studied. The influence of temperature and treatment time on thickness of vanadized layer and its phase composition has been determined. By increasing the temperature and treatment time with V on the steel substrate, the depth of vanadium nitride formed on steel samples changed between 5.16 mum to 16.77 mum. The micro-hardness value of vanadium nitride layers is 1855.8 +/- 74.24 HV0.025. X-ray diffraction analysis showed that the presence phases formed in the vanadium nitride layers on the steel samples are VN and V2N