Controlled hot forming of heat treatment steel grades in the intercritical(gamma-alpha) region

Thermomechanical treatment with its specific methods has contributed substa ntially to the improvement of product quality and the rationalisation of pr oduction. The economic advantages of thermomechanical treatment are obvious ; however, an analysis of the current state of knowledge shows that the pot ential of this method has not yet been exhausted. In this context, controll ed hot forming in the two-phase region is a very promising trend. The first part of this work was dedicated to the microstructural formation, deformat ion behaviour and deformability in the two-phase region. The investigations aimed at clarifying the differences between hot forming in the austenite r egion and the two-phase region, as well as explaining and illustrating spec ial phenomena occurring during hot forming in a region with two major phase s. The second focus of this article is the limit values of rolling technolo gies. The microstructural features and property combinations obtained were assessed by extensive metallographic and material tests. Thermomechanical t reatment in the two-phase region enables the production of advantageous pro perty combinations. (C) 2000 Elsevier Science B.V. All rights reserved.