超高强锚杆钢CCT曲线的测定与分析

Measurement and analysis of CCT curve of ultra-high strength anchor steel

以超高强锚杆钢为研究对象,利用Gleeble-3800型热模拟试验机研究了冷却速度、连续冷却条件对其膨胀曲线的影响,并结合金相-硬度法绘制出该钢的连续转变冷却曲线(CCT曲线)。结果表明:试验钢的临界相变点A_(c1)和A_(c3)分别为732和883℃;在冷却速度为0.5~25℃/s的范围内,随着冷却速度的提高,试验钢在连续冷却转变下的组织产物首先是铁素体,而后依次为珠光体和贝氏体,铁素体所占比例不断减少,珠光体的含量不断增加,并有少量贝氏体形成,硬度逐步增加。

Effects of cooling rate and continuous cooling conditions on the expansion curve of ultra-high strength anchor steel were studied by Gleeble-3800 thermal simulation test machine,and the continuous transformation cooling curves(CCT curve)of the steel were drawn by metallographic hardness method.The results show that the critical transformation points A_(c1) and A_(c3) of the experimental steel are 732℃and 883℃,respectively.In the range of cooling rate of 0.5-25℃/s,with the increase of cooling rate,the microstructure products of the experimental steel under continuous cooling transformation are ferrite,pearlite and bainite in turn,the proportion of ferrite decreases,the content of pearlite increases,a small amount of bainite is formed,and the hardness increases gradually.