COMPARATIVE STRUCTURAL-PHASE ANALYSIS OF MULTI-COMPONENT DIFFUSION CARBIDE COATINGS ON TOOL HIGH CARBON STEEL

Abstract

The results of an analysis of the structure and phase composition of two- and three-component carbide coatings obtained by thermochemical treatment (TCT) are presented in the article. The process of obtaining diffusion carbide coatings includes two stages: 1) preliminary preparation of a saturating mixture by synthesizing metals from oxides in the composition: 98 % (50 % Al₂O₃ + 50 % (70 % Me_xO_y + 30 % Al)) + 2 % NH₄Cl, where Me_xO_y = oxides Cr₂O₃, TiO₂, V₂O₅, MnO₂; 2) TCT of U8 steel (0.8 %) in a synthesized powder mixture at 1100 °C for 6 hours.  The results of carbide layers phase analysis in saturating systems based on Cr-Ti-V, Cr-Ti-Mn, Cr-V-Mn oxides are generalized. Structural and phase-chemical analysis of optimal Cr-V, Ti-Mn, Cr-Ti- V and Cr-Ti-Mn carbide coatings, in which the highest levels of microhardness and wear resistance are achieved. After multi-component diffusion carbide coatings applying, the steel dies operational durability and technical equipment increased by 2–10 times compared to traditional ones.