Improving the quality of gas thermal coatings from wire materials by chemothermal treament

摘要

Structure, phase composition, tribological characteristics and microhardness of CTT-hardened gas-thermal coatings sputtered with low-alloy steel C{sub}B-08 wire coatings were studied. It is shown that the process of CTT of gas-thermal coatings produces thick modified layers accompanied with reduction of iron oxides in these layers. It is concluded that a deeper boronation zone typical for gas-thermal coatings results from high concentration of oxides, pores and interphase boundaries, that generate vacancies and accelerate diffusion transfer of interstitial atoms at saturation. It is established that carbonitration and boronation of C{sub}B-08 steel coatings boosts their wear resistance ≈30 times as compared to untreated coatings and 1.5 and 2 times against cast steel 45 after thermal hardening.