Microstructure Engineering of Thicker Gage Niobium Microalloyed Line Pipe Steel With Enhanced Toughness by High Temperature Processing Using TiN-NbC Composite Precipitate

Prediction of crack arrestability of higher grade line pipe steel microalloyed with niobium in full scale burst tests based on laboratory simulation tests including Charpy impact, DWTT and CTOD is rendered difficult, as the full scale burst test is found to be far more sensitive to microstructure variables than current laboratory tests. This paper deals with nano-scale TiN-NbC composite precipitate engineering as an alternative approach to …