24000TEU集装箱船特厚规格高强船板保心部低温冲击性能研究

Research on low temperature centre impact performance of 24000TEU container ship's special thick and high strength ship plate

为保证24000TEU集装箱船特厚规格高强船板保心部低温冲击性能,采用低碳+Ti+Nb+Ni的成分体系,即可保证强度,亦可保证较高要求的韧性。采用大变形量、低温控轧、DQ模式5 kg水冷,获得以针状铁素体(AF)/贝氏体(B)为主,并有少量的多边形铁素体的多相组织,心部冲击均值达到200 J以上。通过除鳞速度和道次的优化,解决特厚高强船板表面水纹花斑问题。成功研发保心部低温冲击性能的特厚规格高强船板,具有良好的强韧性能、焊接性能和表面质量。

To ensure the low-temperature centre impact performance of the 24000TEU container ship's special-thick and high-strength ship plate,a low-carbon+Ti+Nb+Ni composition system is adopted to ensure both strength and toughness requirements.By using large deformation,low-temperature controlled rolling,and DQ(5 kg-water cooling),a multiphase structure mainly composed of acicular ferrite(AF)/bainite(B)with a small amount of polygonal ferrite was obtained,and the average center impact performance reached over 200 J.By optimizing the descaling speed and pass number,the problem of watermarks on the surface of special-thick and high-strength ship plates is solved.Successfully developed special-thick and high-strength ship plates with low-temperature centre impact performance,which have good toughness,welding performance,and surface quality.