The Paton Welding Journal, 2014, №09



2014 №09 (07)

DOI of Article 10.15407/tpwj2014.09.01

2014 №09 (02)

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The Paton Welding Journal, 2014, #9, 6-16 pages  

DEFORMATION-FREE WELDING OF STRINGER PANELS OF TITANIUM ALLOY VT20

B.E. PATON¹, L.M. LOBANOV¹, V.L. LYSAK¹, V.V. KNYSH¹, V.I. PAVLOVSKY¹, V.P. PRILUTSKY¹, A.N. TIMOSHENKO¹, P.V. GONCHAROV¹ and GUAN QIAO²

¹E.O. Paton Electric Welding Institute, NASU. 11 Bozhenko Str., 03680, Kiev, Ukraine. E-mail: office@paton.kiev.ua
²BAMTRI. Beijing, China. E-mail: guang@cae.cn
 
 
Abstract
Presented are the results of complex of carried out investigations on development of technology for welding by penetration welds of stringer panels of titanium alloy VT20 providing minimum residual stresses and deformations and also high values of their life at cyclic loads. On the full-scale specimens, simulating stringer panels, the penetration welds of T-joints were produced using three methods: electron beam, automatic argon-arc nonconsumable-electrode welding over the layer of activating flux, and automatic argon-arc nonconsumable-electrode welding with immersed arc. To prevent the residual welding stresses and deformations, preliminary elastic deformation of elements being welded was applied. The fatigue tests of all the types of specimens at longitudinal cyclic tension were carried out. The effect of heat treatment, impact mechanical treatment and repair-welding technologies on their fatigue life was also determined. Basing on the results of investigations of full-scale specimens the batches of stringer panels of 1200 mm length were manufactured and tested. The penetration welds, made by argon arc non-consumable electrode welding over the layer of activating flux using preliminary elastic deformation and high-frequency mechanical peening of welds, provide the higher values of fatigue life of welded stringer panels of high-strength titanium alloy VT20 as compared to electron beam welding and argon arc non-consumable electrode welding with immersed arc. The developed technology can be accepted for industrial production of welded stringer panels of high-strength titanium alloys. 14 Ref., 1 Table, 13 Figures.
 
 
Keywords: thin-sheet welded structures, stringer stiffened panels, T-joints, penetration weld, residual stresses and deformations, preliminary elastic deformation, fatigue strength, high-frequency mechanical peening
 
 
Received:                03.12.13
Published:                28.09.14
 
 
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