一、前言近年来国内外对微合金钢控制轧制的研究较为盛行。这主要是因为,它可以把加入微合金元素的作用同轧制工艺结合起来,通过对显微组织的控制来获得所希望的性能。微合金控轧钢的强化机制包括细化晶粒强化,固溶强化,析出强化,位错亚结构强化和织构强化。目前公认细化晶粒强化是既提高强度又改善韧性的唯一强化机制。而铁素体晶粒尺寸的变化又和热变形过程中奥氏体显微组织(奥氏体晶料尺寸,奥氏体晶内的形变亚 I. Introduction In recent years, domestic and foreign research and development of microalloyed steel controlled rolling is more prevalent. This is mainly because it combines the action of adding microalloying elements with the rolling process to achieve the desired properties by controlling the microstructure. The strengthening mechanisms of microalloyed rolled steel include grain refinement, solid solution strengthening, precipitation strengthening, dislocation sub-structure strengthening and texture strengthening. It is currently recognized that the refinement of grain strengthening is the only strengthening mechanism that increases both strength and toughness. The ferrite grain size changes and thermal deformation during the austenite microstructure (austenite crystal size, austenite within the crystal deformation