Avtomaticheskaya Svarka (Automatic Welding), # 5, 2019, pp.18-24
Strain state of welded and brazed units from dissimilar materials with soft interlayer at thermal loading
V.V. Kvasnitsky1, V.F. Kvasnitsky2, M.V. Matvienko2, E.A. Buturlya2, G.V. Ermolaev2
1National Technical University of Ukraine «Igor Sikorsky Kyiv Polytechnic Institute».
37 Pobedy Ave., Kiev-56, Ukraine. Е-mail: kvas69@ukr.net
2National University of Shipbuilding. 9 Heroev Stalingrada Ave., 54025, Nikolaev, Ukraine. E-mail: welding@nuos.edu.ua
Computer modeling using the finite element method was used to study the stress-strain state in joints of homogeneous materials under axial load. The studies were carried out taking into account plastic deformations in soft interlayers, which are usually used in diffusion welding to activate surfaces and reduce residual stresses, and in brazing, as the intermediate interlayer, a brazed weld serves, that differs from the base metal in its physical and mechanical properties. It is shown that along the butt, both in the metals being joined as well as in the interlayer, equivalent stresses are distributed more uniformly than during elastic deformation. Plastic deformations in the interlayer are absent in the zone of stagnation (on the axis of the cylindrical unit) and are almost linearly increased, reaching maximum values (about 6.5%) at the outer cylindrical surface of the unit. A high level of plastic deformations indicates the feasibility of using thermal loading in diffusion welding of dissimilar materials with soft interlayers. The degree of “softness” of the interlayer and its effect on stress-strain state of the unit during plastic deformation is mainly determined by its strength (yield strength) and almost does not depend on its rigidity (elastic modulus). 8 Ref., 10 Fig.
Keywords: welded and brazed units, soft interlayer, computer modeling, stress-strain state, thermal loading
Received: 12.02.2019
Published: 04.04.2019
References
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https://doi.org/10.1007/s11223-017-9882-4