Contribution to Simplified Residual Stress Calculations of Multi-Layer Welds

Contribution to Simplified Residual Stress Calculations of Multi-Layer Welds

J. Klassen, T. Nitschke-Pagel, K. Dilger

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Abstract. Especially for larger structures destructive measuring techniques for residual stress determination can be neglected and non-destructive methods are subject to disadvantages such as the limited resolution. Furthermore, residual stress gradients in the direction of sheet thickness cannot be determined easily. The growing use of FEM, on the other hand, gives an insight into residual stresses at each point of the computed model. However, FEM for residual stress calculation is subject to certain limits and error sources due to the fine discretization and the high degree of non-linearity. In particular, the calculation of multi-layer welds will reach high computation times. This known issue is often counteracted with radical simplification of the numerical model such as lumping or semi-transient method. The result inaccuracies of these methods are rarely quantified and published. To clarify which simplification strategies are applicable in numerical welding simulation reference models were produced and experimentally verified. On this basis, simplification approaches were investigated numerically and their effects on result quality were quantified. It could be shown that most of the commonly used simplification approaches for the calculation of residual stresses and distortions are only partially permissible, if any. Each method has its limits and poses a risk to the user, if certain data for validation and verification are available only to a limited extent. This means that a strongly localized comparison between experiment and calculations is not necessarily a proof of correctness of the calculation approaches if a more refined experimental determination is dispensed with.

Keywords
Residual Stresses, Welding Simulation, X-Ray Diffraction, Neutron Diffraction

Published online 9/11/2018, 6 pages
Copyright © 2018 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: J. Klassen, T. Nitschke-Pagel, K. Dilger, ‘Contribution to Simplified Residual Stress Calculations of Multi-Layer Welds’, Materials Research Proceedings, Vol. 6, pp 251-256, 2018

DOI: http://dx.doi.org/10.21741/9781945291890-40

The article was published as article 40 of the book Residual Stresses 2018

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

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