Effect of processing route and niobium content on the microstructure and properties of low carbon-boron steels

During the past five years there has been research on the direct quenching of low carbon-boron steels to produce a new generation of forging and plate steels. Initial rolling of laboratory scale plates of low carbon Mn-Ti-Al-B steel indicated that the yield strength for these materials is approximately 500 MPa when directly quenched after high temperature multi-pass rolling. In this work torsion testing has been used to examine the effects of finishing temperature, strain (single and multi-pulse), delay time before cooling, cooling rate and Nb on the final microstructure and mechanical properties.