中文摘要：

本文实验研究了轧后冷却方式对低碳钛微合金钢组织、析出行为以及力学性能的影响。结果表明，不同的轧后冷却方式（层流冷却、层流冷却＋超快速冷却、超快速冷却）下实验钢的组织主要是细晶铁素体。与层流冷却工艺相比，采用超快速冷却工艺能够细化铁素体晶粒尺寸，促进微合金元素Ti在铁素体中的析出且细小弥散。采用超快速冷却工艺，实验钢的抗拉强度和屈服强度分别达到了760MPa和683MPa，比层流冷却工艺下实验钢分别提高了40MPa和20MPa。

英文摘要：

The effects of cooling process after rolling on microstructure , precipitation behavior and properties of titanium micro-alloyed high strength steel were researched by using the laboratory rolling test. The results show that fine grain ferrite could be obtained at laminar cooling process, laminar cooling ＋ ultra fast cooling process and ultra fast cooling process. The ultra fast cooling process could improve the grain size of ferrite, promote the finer dispersion precipitation of micro-alloying elements Ti in ferrite. The tensile strength and yield strength of strip are 760MPa and 670MPa by using the ultra fast cooling process, the yield strength and tension strength improved 25MPa and 30MPa respectively compared with laminar cooling strip.