Metallurgical basis for thermomechanical processing of microalloyed steels

The fundamental metallurgy of thermomechanical processing (TMP) has become much better understood over the past decade. An appreciation of the driving forces and retarding forces has led to both a better understanding of existing practices and the development of new practices. Furthermore, the distinction between plate and strip rolling, for example, has become better defined, quantified, and understood. This understanding has led to improved products, increased productivity, and better consistency. The information generated, first in plate and then in strip rolling, is slowly being adopted in the structural rolling and forging industries. Finally, the role of TMP has been extended, with the new ultralow carbon steels, to include the control of stabilisation reactions and texture development during rolling for downstream benefit in the cold mill. This paper reviews the basic physical metallurgy of TMP, discusses various aspects of alloy design, and presents illustrations of modern views of plate processing. (C) 2001 loM Communications Ltd.