论文部分内容阅读
对30MnSi PC钢棒进行了淬火回火处理,分析探讨了热处理工艺对高强度钢耐延迟断裂性能的影响。采用FIP试验作为PC钢棒耐延迟断裂性能的评价方法。研究发现,相同的回火工艺下30MnSi钢的耐延迟断裂性能随淬火温度的升高呈先升高后降低的趋势,950℃左右淬火其耐延迟断裂性能较好;在保证强度满足要求的前提下提高回火温度可以提高钢的耐延迟断裂性能。组织观察发现,经430℃左右回火后,30MnSi钢棒得到的回火索(屈)氏体组织均匀细小,碳化物弥散分布在马氏体板条界上,耐延迟断裂性能较好。可见,通过改变热处理制度改变组织形态,是改善30MnSi钢的耐延迟断裂性能的一种有效途径。
The 30MnSi PC steel bar was quenched and tempered to analyze the effect of heat treatment on the delayed fracture resistance of high strength steel. FIP test was used as a method to evaluate the delayed fracture resistance of PC steel bar. The results show that the delayed fracture resistance of 30MnSi steel first increases and then decreases with the increase of quenching temperature under the same tempering process. The delayed fracture resistance of quenched steel is better at the same tempering temperature, and it improves under the premise of ensuring the strength meets the requirements Tempering temperature can improve the delayed fracture resistance of steel. Tissue observation showed that after tempering at about 430 ℃, the microstructure of the tempering wire obtained by 30MnSi steel bar was uniform and fine, and the carbides distributed in the martensite slab boundary with good delayed fracture resistance. Can be seen by changing the heat treatment system to change the morphology of the organization, is to improve the 30MnSi steel delayed delamination performance of an effective way.