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rn在Formastor-F试验机上进行热模拟试验,采用膨胀法测定了耐蚀钢轨U68CuCr临界点及在0.1～5.0℃/s的冷却速度下连续冷却的温度膨胀曲线,结合微观组织和显微维氏硬度分析,采用Origin软件绘制出连续冷却转变(CCT)曲线。试验结果表明,耐蚀钢轨U68CuCr冷却速度不超过0.1℃/s时,可获得索氏体+珠光体组织;冷却速度达到2.0℃/s时,钢中出现马氏体组织;当冷却速度达到5.0℃/s时,得到片间距更细小的屈氏体组织,过冷奥氏体转变为马氏体+屈氏体组织。根据连续冷却转变曲线,为优化耐蚀钢轨轧后冷却工艺提供理论依据。“,”Hot simulation test is carried out in the Formaster-F test machine using the newly developed corrosion resistant steel rail U68CuCr as the test piece,the critical point of the corrosion resistant steel rail U68CuCr and the continuous cooling temperature dilation curve at the 0.1~5.0 ℃/s cooling rate are measured out by application of the dilation method,and the continuous cooling transformation(CCT)curve is drawn up using the Origin software in combination with analysis on the micro-structure and micro Wickers hardness.Experimental results show that the structure of sorbite-perlite can be found in the corrosion resistant steel rail U68CuCr,when the coolint rate is less than 0.1 ℃/s,and as soon as the cooling rate reaches 2.0 ℃/s,the martensite structure occurs in the steel,and once the cooling rate comes up to 5.0 ℃/s,the troosite structure with smaller slice space appears and the overcooling austenite transforms into martensite+troosite.A theory evidence can be provided for optimization of the cooling process of the corrosion resistant steel rail after rolling according to the CCT curve.