ANALYSIS OF THE CRACK RESISTANCE OF THE TEKKEN-SPECIMEN
DOI:
https://doi.org/10.14529/met180107Keywords:
TEKKEN-specimen, crack resistance, crack, weld joint, cold cracksAbstract
The work is focused on the analysis of the crack resistance of the TEKKEN-specimen during its cooling after welding. The TEKKEN-specimen is manufactured according to GOST 26388–84 type IX and is designed for estimation of propensity of the weld joint's metal to formation of the cold cracks. It was necessary to establish the margin of technological safety of the welded joint and to reveal the critical places of possible cracks. The basis is the principle of assessing the welding stresses with yield stress, obtained by cooling of samples with a high speed typical for a welded joint.
A numerical estimation of a stress level in various points of a welded joint with allowance for a welding mode, conditions of fastening is made in ESI SYSWELD. Dependency graphs of the first main stresses on temperature were built. With a reduction of a crack resistance below one, it is probably the formation of cracks, because in this case the acting stresses exceed the yield stress.
It is shown the most dangerous things are the transition zones from the weld joint to the base metal at a temperature of 1020 Celsius, and the root of the weld joint after full cooling. The developed analysis method of crack resistance can be used to evaluate other typical welded joints and samples.
References
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