核电用钢板热处理工艺的研究

Study on Heat Treatment Process of Steel Plate for Nuclear Power

针对厚度为100 mm的核电用钢板20MnHR-B进行不同工艺热处理和力学性能、显微组织检测分析,结果表明:经过正火+回火处理,钢板的力学性能满足交货状态、最大和最小模拟焊后热处理状态的技术要求;经过最大模拟焊后热处理,钢板获得铁素体+珠光体+少量粒状贝氏体组织。最终将100 mm厚度核电用钢板20MnHR-B的最佳热处理工艺确定为900℃正火+保温1.2 min/mm+水冷、630℃回火+保温2 min/mm+空冷。

Heat treatment of different processes,tests on mechanical properties and microstructure are performed on 20MnHR-B steel plate of 100 mm thickness for nuclear power.The results show the mechanical properties of the steel plate satisfy the technical requirements under delivery condition,max.and min.SPWHT conditions.After max.simulated post weld heat treatment,the test plate microstructure consists of ferrite+pearlite+less granular bainite.The optimum heat treatment process of 20MnHR-B steel plate of 100 mm thickness is determined as 900℃normalizing+holding at 1.2 min/mm+water cooling and 630℃tempering+holding at 2 min/mm+air cooling.