Hot ductility behavior of boron microalloyed steels
Hot ductility behavior of boron microalloyed steels
复制标题
DOI：
10.1016/j.msea.2007.01.098
复制
发表时间：
2007-07
期刊：
影响因子：
6.4
通讯作者：
E. López-Chipres;I. Mejía;C. Maldonado;A. Bedolla-Jacuinde;J. Cabrera
中科院分区：
文献类型：
--
作者：
E. López-Chipres;I. Mejía;C. Maldonado;A. Bedolla-Jacuinde;J. Cabrera
本文分析了硼含量（29 ~ 105 ppm）对硼微合金钢热塑性的影响。为此，在不同温度（700、800、900和1000°C）下以0.001s−1的恒定真实应变速率进行热拉伸试验。在一般情况下，结果表明，在增加硼含量的钢的热塑性的改善。在700、900和1000°C下，延展性高于800°C下的延展性，在800°C下，硼微合金化钢表现出延展性损失的区域（波谷区域）。同样，动态再结晶仅在900和1000°C下发生。试验钢在高温塑性区的断裂表面表明，断裂模式为延性破坏，而在槽区为韧脆破坏。结果进行了讨论，在动态再结晶和硼向奥氏体晶界偏聚，这可能会阻碍形成的先共析铁素体和增加晶界的凝聚力。
The current study analyses the influence of boron contents (between 29 and 105ppm) on the hot ductility of boron microalloyed steels. For this purpose, hot tensile tests were carried out at different temperatures (700, 800, 900 and 1000°C) at a constant true strain rate of 0.001s−1. In general, results revealed an improvement of the hot ductility of steels at increasing boron content. At 700, 900 and 1000°C the ductility is higher than at 800°C, where boron microalloyed steels exhibit a region of ductility loss (trough region). Likewise, dynamic recrystallization only occurred at 900 and 1000°C. The fracture surfaces of the tested steels at temperatures giving the high temperature ductility regime show that the fracture mode is a result of ductile failure, whereas it is ductile–brittle failure in the trough region. Results are discussed in terms of dynamic recrystallization and boron segregation towards austenite grain boundaries, which may retard the formation of pro-eutectoid ferrite and increase grain boundary cohesion.