| || Thermomechanically controlled processing for producing ship building steels
Author : Basu, B.;Tripathi, S. M.;Modak, V. V.
Source : Defence Science Journal ; Vol:55(1) ; 2005 ; pp 91-101
Subject : 623.8 Naval Science
Keywords : Thermomechanically controlled processing;TMCP;HSLA steels;High strength low alloy steels;Steel plates;Quench and tempered steels;Low alloy steels;Structural applications;HICC;ULCB steels;Ship building steels;Microalloyed steels
Abstract : "The thermomechanically-controlled processing of a newly developed high-strength low-alloy steel has been designed in such a way that the problems, normally faced in producing the quench and tempered steels, have been mitigated and the final product (steel plates) are available in as rolled condition rather than quench and tempered steels. A low-carbon, low-alloy steel having nickel, chromium, copper, niobium, boron, has been designed for ease of welding, improved weldability over the conventional steels, and responsive to the thermomechanically-controlled processing. A number of laboratory-scale batches of the alloy were made with different combinations of thermomechanically-controlled processing parameters. The different thermomechanically-controlled processing parameters studied include (i) slab-reheating temperature, (ii) deformation above recrystallisation temperature, (iii) deformation below recrystallisation temperature, and (iv) finish-rolling temperature. The thermomechanically-processed steel plates, under certain combinations of thermomechanically-controlled processing parameters, showed excellent combination of impact and tensile properties. In this paper, the microstructure-property correlation has been made to throw light on the type of microstructure required to obtain such superior package of mechanical properties. Further, the optimised laboratory-scale thermomechanically-controlled processing parameters, which were used to process newer batches of the steel made through industrial route, have delivered encouraging results."