超大型集装箱船用特厚止裂钢的发展

Development of heavy-gauge steel with excellent brittle crack arrest toughness for mega container carriers

超大型集装箱船用特厚止裂钢板由于优异的止裂韧性,能够显著减小复杂交变应力对甲板上部大开口部位形成的安全威胁。通过系统总结止裂韧性的评价体系、对比分析国内外超大型集装箱船舶的发展趋势和特厚止裂钢板的生产状况,综述了超大型集装箱船用特厚止裂钢板的显微组织特征和有可能实施的生产工艺。全厚度细小的等轴铁素体、多边形铁素体配合有限的细化贝氏体及心部γ线上的织构强化是改善特厚钢板止裂韧性的关键。东北大学提出的NEU-Rolling控轧工艺能够解决TMCP态特厚止裂钢板的生产难题。

For the excellent brittle crack arrest toughness,the heavy-gauge steel for mega container carriers can significantly reduce the hazard factor caused by complex alternating stresses on a large opening structure on the upper deck.By systematically summarizing the evaluation system of crack arrest toughness,comparing and analyzing the development trend of mega container carriers at home and abroad as well as the production status of heavy-gauge crack arrest steel,the microstructural characteristics and possible production process are summarized.The finegrained equiaxed ferrite,polygonal ferrite,limited refined bainite,combined with the strengthened texture along with theγorientation at 1/2 thickness are the keys to improving the crack arrest toughness.The NEU-Rolling process proposed by Northeast University can solve the existing problem of producing heavy-gauge steel by a traditional controlled rolling process.