摘要
为提高厚规格海工钢低温冲击韧性,使其获得良好的强韧性匹配,对某钢厂生产的80 mm厚EH36钢板的轧制与水冷工艺进行研究,实现对钢板组织的调控,达到优化厚规格海工钢强韧性匹配,提升低温冲击韧性的目的。试验采用了7种不同轧制与水冷工艺,并对试制钢板进行了拉伸性能试验、冲击性能试验以及金相组织观察。结果表明:在低碳微合金化的化学成分体系下,粗轧阶段至少2道次压下率大于10%、中间坯厚度为2h以上(h为成品钢板厚度),控制精轧终轧温度小于800℃、终冷温度小于300℃,可获得细化的针状铁素体、贝氏体组织,钢板强韧性匹配良好。进一步,将钢板在冷却前进行弛豫处理,再水冷至300℃以下,析出一定比例的先共析铁素体,并使组织得到进一步均匀与细化,使钢板冲击韧性得到了进一步提升。
To improve the low-temperature impact toughness of thick gauge offshore steel and achieve an excellent strength-toughness balance,the rolling and water cooling processes of 80 mm thick ness EH36 plates produced by a factory were studied.By regulating the microstructure through seven different processing schemes,the aim was to improve the strength-toughness match and low temperature impact toughness.Tensile tests,impact tests,and metallographic observations were conducted on the trial plates.The results indicate that with a low-carbon microalloyed chemical composition,by ensuring at least two passes with a reduction rate exceeding 10%during the roughing rolling stage,an intermediate slab thickness of over2h(where h is the thickness of the finished steel plate),controlling the finishing rolling temperature below 800℃,and the final cooling temperature below 300℃,a refined acicular ferrite and bainite microstructure can be obtained,resulting in a good strength-toughness match of plates.Further optimization was achieved by introducing a relaxation treatment before water quenching to 300℃,which promotes precipitation of proeutectoid ferrite and enhances microstructure uniformity.This dual-process strategy significantly improved the impact toughness of the plate.
作者
宋继强
白学飞
马林
王彦龙
张小宇
徐鑫
SONG Jiqiang;BAI Xuefei;MA Lin;WANG Yanlong;ZHANG Xiaoyu;XU Xin(Rizhao Steel Yingkou Medium Plate Co.,Ltd.,Yinkou 115000,China;Liaoning Medium Plate Professional Technology Innovation Center,Yinkou 115000,China;Liaoning Provincial Enterprise Technology Center,Yingkou 115000,China)
出处
《轧钢》
北大核心
2025年第2期115-121,共7页
Steel Rolling
关键词
海工钢
厚规格
低温冲击韧性
水冷工艺
组织调控
offshore steel
thick gauge
low-temperature impact toughness
watercooling process
microstructure control
