高性能18MND5核电钢板的强韧化探索

Exploration of Strengthening and Toughening of High-performance 18MND5 Nuclear Plate for Power Station

为满足华龙一号堆型中低温设备对Mn-Ni-Mo系钢板的性能要求,通过优化合金成分设计,调整淬火、回火热处理参数等工艺手段,研发出高性能18MND5核电钢板。对试制钢板的试验研究结果表明:适当提高强化元素、加入适量细化晶粒元素Al和微量强碳化物形成元素V,可以得到细小且稳定的显微组织,有利于提高材料强度;选择合理的淬火温度、保证较高的冷却速度,可获得细小的马氏体组织,经回火后钢板获得较好的低温韧性及较低的无塑性转变温度。试制出的高性能18MND5核电钢板可以满足华龙一号堆型中低温设备的设计要求。

In order to meet the property requirement of Mn-Ni-Mo steel plate of HUALONG No.1 nuclear power station reactor,we developed the high-performance 18MND5 nuclear plate by optimizing the design of alloy composition and adjusting the parameters of quenching and tempering heat treatment.The test results show that the fine and stable microstructure can be obtained by properly increasing the strengthening element,adding an appropriate amount of refined grain element Al and adding a small amount of strong carbide forming element V,which is conductive to improving the strength of the material.Fine martensite structure can be obtained by choosing a reasonable quenching temperature and ensuring relatively high cooling rate and the plate have better low temperature toughness and lower non-plastic transition temperature after tempering.The trial produced high-performance 18MND5 nuclear plate can meet the design requirements of HUALONG No.1 nuclear power station reactor.