论文部分内容阅读
为研究合金元素钼、铬对低碳铌钛微合金钢连续冷却转变行为的影响,采用Gleeble-3800热模拟试验机和热膨胀试验方法,测定了钼、铬含量不同的3种低碳铌钛成分微合金钢在不同冷却速度下的相变点,采用光学显微镜及扫描电子显微镜观察了其转变产物的微观组织,同时结合维氏硬度测试,绘制了动态CCT曲线。结果表明,钼和铬均降低奥氏体向针状铁素体转变的相变温度,并且在冷速大于1℃/s时,钼比铬的作用效果更加明显。钼、铬均能抑制先共析铁素体和珠光体的转变,扩大针状铁素体形成冷速范围,并能够显著细化组织。
In order to study the effect of alloying elements molybdenum and chromium on the continuous cooling transformation of low carbon niobium titanium microalloyed steel, three kinds of low carbon niobium titanium components with different molybdenum and chromium contents were determined by Gleeble-3800 thermal simulation test machine and thermal expansion test method Micro-alloyed steel at different cooling rate of the transformation point, the use of optical microscopy and scanning electron microscopy of the microstructure of its transformation products, combined with the Vickers hardness test, draw a dynamic CCT curve. The results show that both molybdenum and chromium reduce the transformation temperature of austenite to acicular ferrite, and molybdenum is more effective than chromium at cooling rates greater than 1 ℃ / s. Both molybdenum and chromium can inhibit the transformation of proeutectoid ferrite and pearlite, broaden the range of acicular ferrite formation speed, and can significantly refine the organization.