Automatic Welding, 2023, №02



2023 №02 (02)

DOI of Article 10.37434/as2023.02.03

2023 №02 (04)

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Avtomaticheskaya Svarka (Automatic Welding), #2, 2023, pp. 18-23

Investigations of the structure of welded joints of polymers using the Rehbinder effect

M.G. Korab, M.V. Yurzhenko, M.O. Kovalchuk, L.S. Parshutina, O.M. Chukashkin

E.O. Paton Electric Welding Institute of the NAS of Ukraine. 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine. E-mail: office@paton.kiev.ua

Welds of polymeric materials, butt welded with a heated tool, are distinguished by a variety of structural components. Investigations of such welds allow studying the general fundamental processes of structure formation in the formation of welded joints of polymers. In this work, mechanical tests of welded joints of polymer pipes with a local load in the environment of surface active substances and with the use of the Rehbinder effect were carried out. Experimental specimens of pipe joints with a diameter of 63, 90, 110 and 160 mm from PE80 polyethylene were produced in the standard equipment for butt welding with a heated tool on the modes recommended by DBN B.2.5-41:2009. The tests were carried out in accordance with the requirements of the international standard ISO 22088 “Cracking under the influence of the environment” (ESC). The characteristic features of cracks propagation in the tests of the base material and the fusion zone of the weld were investigated. Using optical microscopy, the fracture surfaces of the specimens were investigated immediately after tests and after chemical etching in sulfuric acid solution. It was shown that in the fusion zone, a weakened “blurry” structure of polymeric material is formed, which is fractured during a local load. 14 Ref., 10 Fig.
Keywords: butt welding with a heated tool, supramolecular structure, mechanical tests, fracture surfaces


Received: 02.01.2023

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