Abstract：The effect of boron on the microstructure and mechanical properties of high strength steels with low welding crack sensitivity, in the conditions of TMCP, TMCP+T and QT, respectively, were investigated. The result shows that boron improves the hardenability by suppressing the formation of proeutectoid ferrite. The microstructure of the boron-bearing steel, in the state of TMCP, consists of coarse bainite and martensite, and the prior austenite grain boundaries are retained. The QT process leads to a microstructure of tempered sorbite, but the boron-bearing steel exhibits lower fraction of high angle grain boundaries than the boron-free steel. A significant increase in strength, namely tensile strength by 300, 214 and 101MPa and yield strength by 320, 259 and 144MPa, respectively, for the above mentioned three conditions, but decrease in elongation and impact toughness, by the addition of boron, is observed. The best combination of strength and toughness is found to be achieved by QT process for the boron-free steel and TMCP+T process for the boron-bearing steel.
杨汉，王西霞，曲锦波. 硼对低焊接裂纹敏感性高强钢组织性能的影响[J]. 钢铁, 2013, 48(12): 80-84.
YANG Han,WANG Xi-xia,QU Jin-bo. Effect of Boron on the Microstructure and Properties of High Strength Steels With Low Susceptibility to Weld Cracking. Iron and Steel, 2013, 48(12): 80-84.
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2013, Vol. 48 
