An approach to triangular induction heating in final precision forming of thick steel plates

An automatic high-frequency (HF) induction-heating (IH)-based triangular heating process was introduced in order to investigate the influence of designing heating patterns on the permanent deformation behavior of an SS400 thick plate. Temperature distribution and permanent plate deformation during triangular heating were predicted based on electromagnetic–thermal and thermal–structural analyses, respectively. Both analytical and experimental permanent deformation values obtained by zigzag-type triangular heating were significantly higher than those by fan-shaped triangular heating, presumably because of the different temperature gradient along the thickness. Proper design of triangular heating pattern appeared to be the most important factor in determining the final shape of the thick plate. All predicted results were in good agreement with the experimentally observed permanent deformation.