轧制工艺对高强度船板组织及性能的影响

Effect of rolling process on microstructure and properties of high strength ship plate

采用不同控轧控冷技术,以不同轧制工艺生产的20 mm厚的钢板进行试验。利用金相显微镜、扫描电镜对其微观组织及夹杂物进行表征分析,拉伸试验机、冲击试验机对力学性能进行分析。结果表明:在不同的控轧控冷条件下,微观组织主要以铁素体为主,并存在少量的珠光体,晶粒度8级左右;强度在432~489 MPa之间,延伸率28.5%~36.5%之间;II开温度、终轧温度、入水温度基本保持不变的情况下,随着入水温度降低,屈服强度和抗拉强度逐渐降低;II开温度、终轧温度、入水温度基本保持不变,随着入返红度降低,抗拉强度逐渐降低,屈服强度先降低,随后增加,冲击功和延伸率逐渐增加;返红温度从622℃降低到565℃时,珠光体呈现退化趋势。

This paper carries out the tests on 20 mm thick steel plates produced by different rolling processes using different controlled rolling and controlled cooling technologies.The microstructure and inclusions are analyzed by metallographic microscope and scanning electron microscope,and the mechanical properties are analyzed by tensile testing machine and impact testing machine.The results show that under different conditions of controlled rolling and controlled cooling,the microstructure is mainly ferrite with a small amount of pearlite,and the grain size is about 8.The strength is between 432 and 489 MPa,and the elongation is 28.5%~36.5%.When the opening temperature II,final rolling temperature and water inlet temperature are basically unchanged,the yield strength and tensile strength gradually decrease with the decrease of water inlet temperature.When the opening temperature,final rolling temperature II and water inlet temperature remain basically unchanged,the tensile strength gradually decreases with the reduction of the inlet redness.The yield strength decreases first,then increases,and the impact energy and elongation gradually increase.When the temperature of reddening decreases from 622℃to 565℃,the pearlite shows a degradation trend.