Integrity and Life Assessment of Welded Joints Made of Micro-Alloyed High Strength Steels

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Abstract:

Structural integrity and life of welded joints made of a micro-alloyed low-carbon fine-grained normalised high strength pressure vessel steel, P460NL1 is presented [1]. The researach performed within the scope of this topic involved a large number of experiments, including tensile and bending tests, hardness and toughness, as well as metallography and fractography tests, in order to determine the mechanical properties of the materials and the welded joints in detail, along with their microstructures and their influence on the obtained test results. Specimens cut out of a welded plate with dimensions of 500x500x14 mm were used for the experiments, whereas certain tests required the making of notches in the specimens, inside the heat affected zone, and this welded joint region was the focus of the research. Fatigue experimental tests were based on the assumption that fatigue crack growth rate changes depending on the regions through which the crack passed during its propagation. For this purpose, specimens used in toughness and fatigue tests were divided into four groups, depending on the part of the plate from which they were taken. Numerical calculations were performed using the extended finite element method (XFEM) [2]. Simulations were based on the experimentally determined values of Paris law coefficients, C i m [3-5], for every region through which the crack propagated during each test. Obtained results have indicated good agreement with the experimental ones, which verified the application of extended finite element method in this case.

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161-167

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February 2020

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[1] Simon A. Sedmak: Integrity and life assessment of welded joints made of micro-alloyed high strength steels under static and dynamic loading, Doctoral thesis, Faculty of Mechanical Engineering, University of Belgrade, (2019).

DOI: 10.4028/www.scientific.net/amr.1157.161

Google Scholar

[2] A. R. Khoei: Extended Finite Element Method, theory and applications, Wiley, (2015).

Google Scholar

[3] M. Mikota, S. Staib, S. Schmauder, Ž. Božič, Numerical determination of Paris law constants for carbon steel using a two-scale model, Journal of Physics Conference Series 843.

DOI: 10.1088/1742-6596/843/1/012042

Google Scholar

[4] Lj. Milović et al: Determination of fatigue crack growth parameters in welded joint of HSLA steel, Structural Integrity and Life, Vol. 11, No. 3, (2011).

Google Scholar

[5] E. Dončeva, B. Međo, A. Sedmak: Finite element analysis of fracture resistance parameters for stationary semi-elliptical surface cracks in high strength steel, Structural Integrity and Life, Vol. 15, No. 3, (2015).

Google Scholar

[6] R. Jovičić, S.A. Sedmak, N. Ilić, Lj. Radović, S. Štrbački, M. Antić, Z. Burzić: The impact of groove edge temperature and heat input on the structure and hardness of the heat afected zone of steel P460NL1 welded joint, Vol. 63, No. 3, pp.101-113.

DOI: 10.5937/zzk1803101j

Google Scholar

[7] M. Fujita, K. Kuki: An Evaluation of Mechanical Properties with the Hardness of Building Steel Structural Members for Reuse by NDT, Metals, Vol. 6, (2016).

DOI: 10.3390/met6100247

Google Scholar

[8] S.A. Sedmak, Z. Burzić, S. Perković, R. Jovičić, M. Aranđelović, Lj. Radović, N. Ilić: Influence of welded joint microstructures on fatigue behaviour of specimens with a notch in the heat affected zone, Engineering Failure Analysis, Vol. 106, (2019).

DOI: 10.1016/j.engfailanal.2019.104162

Google Scholar