Modelling the Local Microstructure Properties due to Multi-Pass Welding

Abstract:

The paper presents an advanced simulation approach developed for considering the local microstructure properties variation due to multiple heat treatment. The model describes the resulting microstructure as a function of the peak temperature, austenisation time, cooling time and takes into account the microstructure formed after each thermal cycle. The model is calibrated with experimental material data obtained by repeated thermal loads. It is qualified to calculate the hardness and local microstructure properties in the HAZ of multi-pass welds. Thermo-mechanical simulation of the residual welding stresses and distortions in multi-pass welded joint is performed and validated by measurements.

• Periodical: Materials Science Forum (Volume 879)
• Pages: 595-600
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.879.595
• Online since: November 2016
• Authors: Gancho Genchev*, Nikolay Doynov, Ralf Ossenbrink, Vesselin Michailov
• Keywords: Microstructure Properties, M-STAAZ, Multi-Pass Welds, Residual Stress, Simulation

References

[1] P. Seyffarth, B. Meyer, A. Scharff, Großer Atlas Schweiß-ZTU-Schaubilder, Fachbuchreihe Schweißtechnik, Bd. 110, DVS Verlag, Düsseldorf, (1992).

DOI: 10.1002/maco.19840351211

[2] H. Gnirss, Beitrag zur Ermittlung der Schweißeignung höherfester niedriglegierter Feinkornbaustähle - Simulation von Temperaturzyklen, TU Braunschweig, Diss., (1973).

[3] H.J. Peetz, Schweißsimulation bis in den schmelzflüssigen Zustand zur Untersuchung von Umwandlungsvorgängen bei hohen Spitzentemperaturen und unter Einwirkung von Wasserstoff, TU Braunschweig, Diss., (1979).

[4] F. Berkhout, P.V. Lent, Anwendung von Spitzentemperatur-Abkühlzeit-(STAZ)-Schaubildern beim Schweißen hochfester Stähle, in: Schweißen und Schneiden 20 (1968), Nr. 6, p.256–260.

[5] R. Ossenbrink, V.G. Michailov, Thermomechanical Numerical simulation with the maximum Temperature austenisation cooling time model (STAAZ), in: Mathematical Modelling of Weld Phenomena 8, Verlag der Techn. Univ. Graz, 2007, p.357 – 372.

[6] R. Ossenbrink, Thermomechanische Schweißsimulation unter Berücksichtigung von Gefügeumwandlungen, Ber. d. Lehrstuhls Fügetechnik d. BTU Cottbus, Bd. 2, Shaker Verlag, Diss., (2009).

[7] Zh. Guo, N. Saunders et al., Modelling phase transformations and material properties critical to the prediction of distortion during the heat treatment of steels, in: Int. J. Microstructure and Materials Properties, Vol. 4, No. 2, 2009, pp.187-195.

DOI: 10.1504/ijmmp.2009.028632

[8] G. Genchev, V.G. Michailov et al., Physical and numerical simulation of the heat-affected zone of multi-pass welds, in: Materials Science Forum, Vol. 762, 2013, pp.544-550.

DOI: 10.4028/www.scientific.net/msf.762.544

[9] D. Deng and H. Murakawa: Prediction of welding residual stress in multi-pass butt-welded modified 9Cr–1Mo steel pipe considering phase transformation effects, in: Comp. Mat. Sc. 37 (2006), p.209–219.

DOI: 10.1016/j.commatsci.2005.06.010

[10] D. Radaj, Welding residual stresses and distortion: Calculation and measurement, second ed., DVS Media, Düsseldorf, (2003).

[11] J. A. Goldak, M. Akhlaghi, Computational Welding Mechanics, Springer, Heidelberg, (2005).

[12] G. Genchev, R. Ossenbrink, N. Doynov, V.G. Michailov, Gefügeeigenschaften in der Wärmeeinflusszone von Mehrlagenschweißungen aus S355J2+N, in: Praktische Metallographie, Sonderband 44, Inventum, 2012, pp.167-172.