轧制道次间插入冷却对特厚钢板组织与性能的影响

使用实验轧机旁冷却装置配合轧机进行轧制实验，研究轧制道次间不同冷却工艺对特厚钢板组织和性能的影响规律.研究结果表明:采用道次间冷却工艺可以在全厚度方向获得组织细化及强韧性提高效果，采用强冷道次间冷却实验钢1/4处晶粒尺寸可细化至10μm，强度为376MPa，-40℃冲击功为169J;心部晶粒尺寸可细化至15μm，强度为360MPa，-40℃冲击功为123J.本工艺可形成470μm厚表层细晶层，晶粒尺寸可细化至5μm;粗轧道次间插入冷却工艺轧制钢板强度和冲击韧性优于中间坯冷却工艺;随冷却强度增加，钢板内部组织明显细化且强度大幅提高.

Effect of Inter-Pass Cooling Process on Microstructure and Properties of Ultra-heavy Steel Plate

By using a cooling device beside the laboratorial rolling mill， an inter-pass cooling(IPC) process was applied during rolling ultra-heavy steel plate. Here， the effect of the IPC process on microstructure and properties of the rolled plate was studied. The results showed that the steel plate has excellent strength and toughness after the IPC process. When the rolled plate is applied by a strong IPC process， the grain size is 10μm， the strength is 376MPa and the impact energy at -40℃ is 169J at the 1/4-thickness， while they become 15μm， 360MPa and 123J respectively at the 1/2-thickness. Meanwhile， a surface ultra-fine grain layer with the thickness of 470μm can be obtained and the average grain size is less than 5μm. The strength and toughness of the rolled plate are better in a strong IPC process than those in the inter-slab cooling process. When the intensity of the IPC process increases， the grain size decreases and the strength increases.