关键词: A387Gr11CL2钢板, 直接淬火, 高温回火, 焊后热处理, 组织, 力学性能

Abstract: Direct quenching process of A387Gr11CL2 steel plate was carried out on the heavy plate production line, followed by tempering experiment at different temperatures. The results show that the direct quenching+tempering process can obtain the steel plate whose properties meet the requirements of the ASTM A387/A387M-17 standard, and the best tempering process is tempering at 750-760 ℃ for 100 min. When tempered at 740-750 ℃, the boundaries of the lath in the microstructure are clear, and there are large number of small carbides on the interface of the lath. When tempered at 760 ℃, the boundaries of the lath gradually disappear, while the carbides still exist. When tempered at 780 ℃, the laths merge and widen, and the carbides completely disappear. After the simulated post welding heat treatment, the strength and hardness of the tested steel plate decrease slightly, but there is no significant change in the impact absorbed energy at -30 ℃.

Key words: A387Gr11CL2 steel plate, direct quenching, high temperature tempering, post weld heat treatment, mechanical properties