"Grain Refinement - The Powerful Metallurgical Solution for High Performance Steels "

by "Dr. Bian Jian "

Publisher - "Niobium Tech Asia, Singapore & CBMM, Brazil "

Category - Engineering & IT

"Steel properties are predominantly influenced by microstructural features. These microstructural features like phase constitutes as well as their volume fraction, distribution and size can be significantly improved through grain refinement during the manufacturing processes. It is well known today that grain-refined steels demonstrate superior properties to conventional ones in the aspect of strength, toughness, formability, weldability and durability in terms of fatigue and wear resistance. The development history of Nb metallurgy has clearly demonstrated that thermomechanically controlled process (TMCP) tailored with Nb microalloying is the most effective and practical way to achieve grain refinement compared to microalloying of Ti and V. Therefore, Nb micro-alloyed steels have been widely produced for different applications in the different segments for several decades. Today the Nb metallurgy for high strength steels such as low carbon microalloyed steels (HSLA) and advanced high strength steels for automotive application and for oil and gas transportation are well established and routinely practiced. This paper will explain the fundamentals of grain refinement through Nb microalloying and its impact on microstructural evolution and resulted property and performance improvement of commonly produced steel grades containing different microstructures regardless of ferrite, perlite, bainite, martensite or even multi-phase microstructure of advanced high strength steels. "

Please login to borrow the book.