中文摘要：

运用SEM、TEM、EDX及析出物定量分析等方法，通过实验室模拟热送热装工艺，研究了X80管线钢坯分别在750℃和1100℃热装轧制时微合金元素的固溶和析出情况。结果表明，1100℃热装的钢板轧前钢坯中Nb、V、Ti等微合金元素固溶量较高，在轧制和卷取过程中析出充分，且10nm以下析出颗粒所占比例较高，而750℃热装的钢坯中微合金元素固溶量明显低于1100℃热装的钢坯，其轧后钢板中18～36nm析出颗粒所占比例较高。因此，1100℃热装可以充分发挥微合金元素的析出强化作用。

英文摘要：

By using SEM, TEM, EDX and quantitative analysis of precipitates, and simulating the hot charge rolling of Nb-V-Ti-Mo series low carbon microalloy steel in laboratory, the solution and precipitation of microallyed elements during roiling had been investigated at hot charging temperature 750℃ and 1100℃,respectively. The results show that ,before rolling the microallying elements, such as Nb, V and Ti, of the casting ingot hot charged at 1100℃ have higher solid solution quantity. After rolling and curling, there is higher proportion of precipitated particles with the size of less than 10 nm. Whereas the solid solution quantity of the casting ingot hot charged 750℃ is obviously lower than that at 1100℃, and the dominant size of precipitated particles is from 18 to 36 nm. The resuhs indicate that the precipitation strengthening can be displayed thoroughly when hot charged at 1100 ℃.