碳含量对贝氏体型冷作强化非调质钢的组织和力学性能的影响

Effect of Carbon Content on Structure and Mechanical Properties of Cold Hardening Microalloyed Bainite Steel

研究了0.09%～0.14%C含量对5%～50%冷拔减面率和100～500℃2 h时效处理的2Mn-0.003B-0.05Ti非调质钢组织和力学性能的影响。结果表明,当碳含量较低(0.09%～0.12%C)时,可获得比较细小均匀的粒状贝氏体组织,但当碳含量为0.14%时,则组织中出现块状铁素体;在相同的拉拔减面率下,随着碳含量的增加,该钢的强度提高,塑性降低,当减面率较大时,这种差别比较明显;随着碳含量的升高,时效处理后的该钢强度增量明显降低。

Effect of 0. 09% - 0. 14% C content on structure and mechanical properties of 2Mn-O. 003B-0. 05Ti micro- alloying steel cold drawn with 5% -50% reduction and aged at 100 ~500 ℃ for 2 h has been studied. Results show that with lower carbon content （0. 09% -0. 12% C）, the finer and uniform distributed granular bainite structure in steel is ob- tained, while with 0. 14% C, the lumpy ferrite shall occur in structure; at same cold-drawing reduction, with increasing carbon content the strength of steel increases and plasticity decreases, and the larger the reduction, the more significant the tendency; and with increasing carbon content the increment of strength of steel aged obviously decreases.