High strength low alloy steels

High strength low alloy (HSLA) steels have provided better mechanicalproperties and greater resistance to atmospheric corrosion than conventional carbon steels. HSLA steels have yield strength greater than 275 MPa. Chemical compositions are varied to meet mechanical property requirements, e.g. adequate formability and weldability of sheets and plates require 0.05-0.25 % C, 2% Mn and small quantities ofdifferent combinations from Cr, Ni, Mo, Cu, N, V, Nb, Nb, Ti and Zr. Interplay of micro-addition, their segregation behaviour and strengthening have been studied for longproducts. Precipitation in cast, reheated and heat-treated state has been reviewed in response to effects of inter-depletion of interstitial constituents and contribution of micro-alloy elements