Numerical Simulation of Induction Heating of Carbon Steel tubes in Transient Liquid Phase Bonding Process

DI LUOZZO N.; FONTANA M.; ARCONDO B.

Oviedo

Conferencia; International Symposium on Metastable, Amorphous and Nanostructured Materials (ISMANAM 2011); 2011

Universidad de Oviedo

The transient liquid phase bonding process is been performed to join carbon steel tubes, using Fe96.2B3.8 wt% amorphous ribbons of thickness a = 20 µm have been employed as filler material. The tubes are aligned with their butted surfaces in contact with the amorphous layer. The joint is placed into a high frequency induction heating coil under Argon atmosphere. The temperature is raised at the highest possible rate to the process temperature (1250 ºC) and then held for a predetermined time. In this paper, the numerical simulations of the heating stage of the bonding process have been made using the finite element method. This method had shown of being able to deal with these kind of coupled problems: electromagnetic field generated by alternating currents, eddy currents generated on the steel tube, heating of the steel tube due to joule effect and heat transfer by conduction, convection and radiation. The experimental heating stage, for its further simulation, was done with carbon steel tubes. In particular, we are interested in the temperature evolution of the tube upon heating: time to reach the process temperature at the joint, temperature gradient differences between the inner and outer surface of the tube, especially at the joint and the extension of the heat affected zone, taking into account the ferromagnetic-paramagnetic transition. The numerical simulations are validated by comparison with infrared radiation thermometer measurements of the outer surface of the tube at remarkable positions (e.g.: the joint, the zone at the end of the joint, etc.).