Tian Songya, Xu Fan, Zhang Genyuan, Saifan Adnan, Saleh Bassiouny, Li Xiaobo
College of Mechanical and Electrical Engineering, Hohai University, Changzhou 213022, China.
Mechanical Engineering Department, Faculty of Engineering, Sana'a University, Sana'a 12544, Yemen.
Materials (Basel). 2021 Sep 16;14(18):5336. doi: 10.3390/ma14185336.
Weld and base metals require hot or cold working during the steel equipment manufacturing process. As a result, the components should be subjected to a normalizing heat treatment in order to recover their mechanical properties. In this study, the submerged-arc welding of the high strength low alloy (HSLA) thick steel plate(13MnNiMoR) is adapted for the vessel head under the normalizing and tempering heat treatment. The findings showed that the material toughness decreases after heating to simulate a vessel head forming process. The stamping process is carried out under the conditions of 980 °C for one hour, normalizing at 920 °C for 1 h and tempering between 600-660 °C for 2 h, respectively. The martensite-austenite (M-A) constituent is distributed in granular bainite and the boundary of austenite in island constituent. Therefore, it was deemed to be the most detrimental to Charpy-V impact toughness. Between normalizing and tempering, intercritical normalizing at 740 °C was added. As a result of the ferrite with fine particles M-A constituent, the toughness increases significantly.
在钢铁设备制造过程中，焊接金属和母材需要进行热加工或冷加工。因此，部件应进行正火热处理以恢复其机械性能。在本研究中，采用高强度低合金（HSLA）厚钢板（13MnNiMoR）的埋弧焊对容器封头进行正火和回火热处理。研究结果表明，模拟容器封头成型过程加热后，材料韧性降低。冲压过程分别在980℃保温1小时、920℃正火1小时和600 - 660℃回火2小时的条件下进行。马氏体 - 奥氏体（M - A）组元分布在粒状贝氏体和岛状组织的奥氏体边界处。因此，它被认为对夏比V型冲击韧性最不利。在正火和回火之间，增加了740℃的亚临界正火。由于形成了具有细小颗粒M - A组元的铁素体，韧性显著提高。
