• DOI:10.1115/1.2338050
• Corpus ID: 73594981

Simulation of the Distortion of Long Steel Profiles During Cooling

@article{Pietzsch2007SimulationOT,
  title={Simulation of the Distortion of Long Steel Profiles During Cooling},
  author={Robert Pietzsch and M. Brzoza and Yalçın Kaymak and Eckehard Specht and Albrecht Bertram},
  journal={Journal of Applied Mechanics},
  year={2007},
  volume={74},
  pages={427-437}
}

• R. Pietzsch, M. Brzoza, +2 authors A. Bertram
• Published 1 May 2007
• Materials Science
• Journal of Applied Mechanics

Quenching processes are applied to long steel profiles after the rolling process to produce profiles with reliable service properties. The typical problem is the distortion that is occurring upon residual stresses. Profile distortion should be eliminated as it leads to rework expenditure and creates problems associated with bearing and bundling. Moreover, the residual stresses should be controlled to prevent the crack initiation. The modeling of the cooling process is difficult due to the complicated couplings among different physical and mechanical processes 1. The main reason for the distortion is the inhomogeneity of the temperature profile during the cooling process which results in residual stresses, varying phase fractions, etc. 2. The cooling distortion of railway profiles has already been extensively investigated by experiments. An overview of the works can be found in the literature 3, where the experimental results for the residual stresses and deformations after quenching are presented. The distortion and residual stresses in carburized thin strips are investigated by Prantil et al. 4. The thermoplasticity and metallurgical transformations establish the fundamental part of the problem. The distortion is due to transformation-induced stresses and thermal stresses. The phase transitions, temperature, and stresses must be accurately simulated to determine the distortion. If the temperature and cooling conditions are constant in the axial direction of the profile, all the other fields are also constant. Consequently, a 2D mathematical model with fewer degrees of freedom is enough for the simulations. This reduction of the dimension simplifies not only the visualization of the fields, but also the determination of the optimal cooling conditions. This work indicates that the distortion can be significantly reduced by an intensified cooling of the mass lumped parts of the cross section. The atomized spray quenching technique 5,6, where the spraying water is atomized into fine droplets by means of compressed air, is suitable to intensify the cooling of the mass lumped regions, since the vapor film, which occurs in other quenching techniques, is avoided. In this way the mass lumped regions of the workpieces can be cooled more intensively than the edges. Consequently, a uniform temperature distribution on the surface and a reduced stress distribution inside the body with reduced distortion can be obtained.