Влияние концентрационно-временных условий наводороживающего отжига на насыщение водородом титанового сплава ВТ23

Abstract

Kinetics of the processes of volumetric and surface unidirectional absorption of hydrogen by two-phase (α+β) — titanium alloy VT23 (Ti—Al—Mo—V—Fe—Cr) at a temperature of 800 °C in the concentration range from 0.2 to 0.8% (wt.) has been studied. It is established that by varying the concentration of introduced hydrogen during volumetric hydrogenation annealing, it is possible to form structures in the volume from three-phase (α+α′′+β) to single-phase β. It is shown that by changing the conditions of hydrogenation and using barrier coatings, it is possible to control the depth of hydrogen penetration and, consequently, the completeness of the α→β transformation, forming a unidirectional gradient structure changing from (α′′+β) at the side of the «entrance» of hydrogen to (α+β) at the opposite one. It is noted that the absorption of 0.6% (wt.) hydrogen during unidirectional surface hydrogenation proceeds 20 times slower than during volumetric hydrogenation. It was established that with unidirectional surface hydrogenation, the hydrogen content in the near-surface layers was 0.2% (wt.) higher than the introduced hydrogen concentration calculated for the sample volume.