Microstructural, mechanical and magnetic-properties of high-strength low-alloy steel

Studies have been carried out on commercial grade high-strength low-alloy steel, microalloyed with Nb, V and Ti with a view to developing high-strength material with moderate soft magnetic properties. In order to obtain a suitable microstructure necessary for achieving the desired mechanical strength and magnetic properties, spheroidisation annealing (SA) as well as quenching and tempering (QT) treatments have been employed. At longer annealing or tempering time (greater-than-or-equal-to 30 h), both the SA and QT samples have shown ample spheroidisation of carbides resulting in considerable improvement in the magnetic properties without much deterioration in mechanical strength.