Effect of alloying on microstructure and mechanical properties of bainitic high strength plate steels

Abstract

The X-80 steel chemistry has been modified by increased Mn, Cr and Mo that decrease B_S, and two groups of leaner base chemistries have been used with low carbon (LC) and high carbon (HC) that correspond to 0·04 and 0·07 wt-%C respectively. The alloy design approach is to lower B_S and to provide offsetting decreases to the carbon equivalent P_cm and alloy mix cost. The final microstructures of plate steels, their tensile and toughness properties were obtained. The effects of alloying on the evolution of final microstructure and mechanical properties were discussed.