COMBINED PLASMA AND THERMAL TREATMENT OF THE NbC/AISI T1 STEEL SYSTEM

Abstract

Combined plasma and thermal treatment of the NbC/AISI T1 steel system was carried out to improve the strength characteristics of T1 steel. The X-ray diffraction analysis, scanning electron microscopy, energy dispersion microanalysis, and microhardness measurements were used for investigation of the modified layer structure and properties. The findings showed that the treatment of the NbC/T1 steel system by compression plasma flows generated in nitrogen atmosphere led to the dissolution of carbides, formation of ε-NbN nitride, and to a decrease in the steel microhardness. Subsequent annealing in air of a plasma-treated sample for 9 h at a temperature of 600oC resulted in a 1.3 times increase of microhardness compared to the initial steel sample.