Dependence of surface hardening of ВТ22 titanium alloy on nitriding regime combined with thermal treatment

Keywords

two-phase titanium alloy, heat treatment, nitriding, surface engineering, surface hardening.

Cite as

Lavrys S. M. and Pohrelyuk I. M. Dependence of surface hardening of VT22 titanium alloy on nitriding regime combined with thermal treatment. Physico­chemical Mechanics of Materials. 2022. 58(2), 053-058.

Abstract

We study the influence of the time of holding in the course of nitriding combined with hardening heat treatment (HHT) on the surface hardening of VT22 two-phase titanium alloy (Ti–5Al–5Mo–5V–1.5Cr–1Fe). It is shown that a two-phase nitride layer (Ti₂N and TiN) is formed on the surface as the time of holding increases (either in the first stage, or in the second stage, or in both stages of HHT). At the same time, in both stages of HHT, the intensity of nitride formation, as well as the surface microhardness, and the depth of the hardened layer simultaneously increase (up to 8.5 GPa and 30 μm, respectively).

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