低碳钢中纳米尺度沉淀相的透射电子显微术研究(英文)

Electron microscopic study on nano scaled precipitation in low carbon steels

本文用电子显微镜技术对CSP工艺生产的普通低碳钢进行了研究 ,实验结果表明在试样中形成了大量细小的弥散沉淀粒子 ,电子衍射与XEDS分析证实这些沉淀是具有尖晶石结构的氧化铁以及硫化物 ,氧化物尺寸在 2 0nm以下 ,大量分布在晶界和位错上。晶界上还有尺寸在 1 0 0～ 4 0 0nm左右的硫化物粒子。这些沉淀使低碳钢的强度提高近一倍 。

Much research works have been carried out on the low carbon steels produced by CSP (Compact Strip Production) process. Results of the electron microscopy study showed that there exists large number of fine dispersive precipitates in the experimental steels. Their dimension is smaller than 20nm. Electron diffraction and XEDS analysis indicated that these fine precipitates are consistent with spinel structure (Fe 3O 4). These precipitates mainly distribute along dislocations or grain boundaries. Some sulfides with size of about 100～400 nm were also observed at grain boundaries. These fine oxide and sulfide precipitates play a key role in nearly doubling strength of the low carbon steel as well as notable improvement of elongation.