Niobium-Based Alloy Design for Structural Applications: Processing-Structure-Property Paradigm

Abstract

The use of niobium as a microalloying element in high strength steels is now well-known and widely adopted. However, with recent advances in thermo-mechanical processing, inclusive of ultrafast cooling technology, and modifications in alloy design, niobium continues to provide significant mechanical property and processing benefits. With this in perspective, we describe here the footprint of niobium in the new generation of high strength microalloyed steels that involve low carbon-based alloy design approach. In this regard, we underscore the effectiveness of niobium in low carbon-Nb (or low C-Nb-Ti) microalloyed steels in terms of obtaining superior mechanical properties and cost-effectiveness, using recent experiences in the processing of microalloyed steels. Also, elucidated are precipitation and microstructural characteristics when niobium is used as a standalone microalloying element or in conjunction with titanium and molybdenum.