采用Gleeble-3500型热模拟试验机测定了两种X80管线钢（不合钒和含钒）热变形后过冷奥氏体连续冷却转变曲线（CCT），用光学显微镜观察了试验钢在不同速率冷却后的组织，并分析了钒对该钢连续冷却相变动力学的影响。结果表明：两种试验钢在试验冷速范围内均可以获得针状铁素体；添加微量钒可以促进珠光体相变，降低多边形铁素体的相变开始温度和针状铁素体的相变终止温度，对高冷速（大于2℃·s^-1）下针状铁素体的相变开始温度影响不明显，但使低冷速下针状铁素体相变开始温度降低；钒的加入还使相变组织得到了细化。%In this paper, the overcooling austenite continuous cooling transformation curves （CCT） of two kinds of X80 pipeline steels （without vanadium steel and with vanadium） after thermal deformation were determined by Gieeble-3500 thermal simulator. The microstructure of the samples at different cooling rates was observed through the optical microscopy. Furthermore, the effect of vanadium on the continuous cooling transformation kinetics of the steel was discussed. The results show that acicular ferrite could be obtained in the two kinds of steels within experimental cooling rates. Element vanadium could accelerate the phase transformation of pearlite, decrease the transformation start temperature of polygonal ferrite and the transformation finish temperature of aeicular ferrite. However, the addition of vanadium had little influence on the transformation start temperature of aeicular ferrite at high cooling rate（〉2℃·s^-1） and dropped the phase transformation start temperature at low cooling rate. In addition, element vanadium could refine the phase transformation structure.
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