Impact of Magnetic-Pulse and Chemical-Thermal Treatment on Alloyed Steels’ Surface Layer

Abstract

The relevant problem is searching for up-to-date methods to improve tools and machine parts’ performance due to the hardening of surface layers. This article shows that, after the magnetic-pulse treatment of bearing steel Cr15, its surface microhardness was increased by 40–50% compared to baseline. In this case, the depth of the hardened layer was 0.08–0.1 mm. The magnetic-pulse processing of hard alloys reduces the coefficient of microhardness variation from 0.13 to 0.06. A decrease in the coefficient of variation of wear resistance from 0.48 to 0.27 indicates the increased stability of physical and mechanical properties. The nitriding of alloy steels was accelerated 10-fold that of traditional gas upon receipt of the hardened layer depth of 0.3–0.5 mm. As a result, the surface hardness was increased to 12.7 GPa. Boriding in the nano-dispersed powder was accelerated 2–3-fold compared to existing technologies while ensuring surface hardness up to 21–23 GPa with a boride layer thickness of up to 0.073 mm. Experimental data showed that the cutting tool equipped with inserts from WC92Co8 and WC79TiC15 has a resistance relative to the untreated WC92Co8 higher by 183% and WC85TiC6Co9—than 200%. Depending on alloy steel, nitriding allowed us to raise wear resistance by 120–177%, boriding—by 180–340%, and magneto-pulse treatment—by more than 183–200%.

Composition, Structure, and Properties of Ti, Al, Cr, N, C Multilayer Coatings on AISI W1-7 Alloyed Tool Steel

“…Depending on the operational requirements, the gas-phase chemical deposition method is applied to the carbide plates with mechanical fastening multilayer coatings with the participation of TiN, TiC, and Al 2 O 3 compounds [4,9,10]. The arrangement of the layers of compounds in the coating determines the advantage of a particular property.…”

“…Nitrogen in steels or carbide may appear after nitriding. The results of studies on the formation of diffuser carbide and carbon-nitride coatings on tool steels and hard alloys are reported in [9,10]. Literature sources on the formation of TiN, TiC, and Al 2 O 3 diffusive multilayer coatings on tool steels on hard alloys are unknown.…”

“…This is due to the exchange reactions between iron and TiCl 4 chloride. It is possible to assume the possibility of forming diffusion coatings without corrosion destruction of the steel surface during the reactions of titanium chloride disproportionation and elimination of reactions with the formation of iron chlorides [10].…”