Registration Number
0221U106749,
0117U000528
, R & D reports
Title
Surface Engineering two-phase titanium alloys for processing complex formation of functional gradient coating structure
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Head
Pohreliuk Iryna M., Доктор технічних наук
Registration Date
19-12-2021
Organization
Physico-Mechanical Institute named after GV Karpenko of the National Academy of Sciences of Ukraine
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The kinetic regularities of thermodiffusion saturation with nitrogen of titanium alloy VT22 were studied and the main kinetic process constants (kρ, Q, A) for a wide temperature range (750… 950°С) were calculated, which makes it possible to predict nitriding parameters of VT22 alloy Correlation dependences between the parameters of surface plastic deformation and the level of surface hardening of titanium alloy VT22 of different structural state are established. It is shown that increasing the load provides an increase in the level of surface hardening, and increasing the number of passes - improving the quality of the treated surface of the titanium alloy VT22. The influence of the initial structural state on nitriding combined with the hardening heat treatment of VT22 alloy is shown, which in turn affects the structural-phase state and the level of surface hardening of the modified layers. Thus, for the alloy with the original (α + β) - globular and β-structures the level of surface hardening is higher than for the alloy with the original (α + β) -plate. Instead, the most intense structural changes (α-phase growth) are observed in the alloy with the original β- and (α + β) - lamellar structures. The thermal stability of the deformation-strengthened layer under nitrogen saturation conditions up to 820 ° С due to the dominance of solid-soluble nitrogen hardening processes over recrystallization processes has been confirmed. It is shown that pre-surface deformation intensifies nitriding combined with hardening heat treatment of VT22 alloy, which is confirmed by 50% higher surface microhardness and 30% deeper hardened layer compared to nitriding without prior surface deformation. It is established that the deformation-diffusion treatment of titanium alloy VT22 helps to increase its wear resistance in tribological pair with bronze BrAZhN 10-4-4 twice and reduces the coefficient of friction by 30% compared to nitriding without prior surface deformation.
Product Description
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Kravchyshyn Taras M.
Lavrysʹ Serhiy M
Lukyanenko Oleksandr G.
Pohreliuk Iryna M.
Proskurnyak Roman V.
Trush Vasylʹ S
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2021-12-19
