面向不同规格热轧H型钢组织细化的微合金化设计  

Microalloying design for microstructure refinement in hot rolled H-beam steels based on specifications

作　　者：邢军 朱国辉[1] 丁汉林 蒲春雷 王永强 刘淑兰 XING Jun;ZHU Guo-hui;DING Han-lin;PU Chun-lei;WANG Yong-qiang;LIU Shu-lan(School of Metallurgy Engineering,Anhui University of Technology,Maanshan 243002,Anhui,China;Technology Center,Maanshan Iron and Steel Co.,Ltd.,Maanshan 243000,Anhui,China;School of Iron and Steel,Soochow University,Suzhou 215006,Jiangsu,China;Intelligent Development Department,MCC Huatian Engineering and Technology Corporation,Nanjing 210019,Jiangsu,China;College of Physical Science and Technology,Tangshan Normal University,Tangshan 063000,Hebei,China)

机构地区：[1]安徽工业大学冶金工程学院,安徽马鞍山243002 [2]马鞍山钢铁股份有限公司技术中心,安徽马鞍山243000 [3]苏州大学沙钢钢铁学院,江苏苏州215006 [4]中冶华天工程技术有限公司智能化发展部,江苏南京210019 [5]唐山师范学院物理科学与技术学院,河北唐山063000

出　　处：《钢铁》2023年第3期144-150,166,共8页Iron and Steel

基　　金：国家自然科学基金资助项目(52174367);国家重点研发计划资助项目(2021YFB3401003)。

摘　　要：针对厚重热轧H型钢压缩比受限而难以通过“应变诱发相变”机制细化组织的技术难题,提出了利用超细奥氏体晶界促进相变而实现组织细化的新技术。理论分析表明,由于厚重热轧H型钢的压缩比不足以达到“应变诱发相变”所要求的应变积累,如何利用粗轧过程中稳定的第二相粒子抑制奥氏体晶粒长大,并调控精轧过程中奥氏体动态再结晶发生的临界应变,是厚重热轧H型钢微合金化设计中需重点考虑的问题之一。试验结果表明,采用Ti/N微合金化设计可有效抑制加热和粗轧过程中奥氏体晶粒长大,进而达到调控精轧过程奥氏体动态再结晶临界应变、促进有限应变量下的奥氏体动态再结晶而实现组织细化的目的。同时,Ti/N微合金化设计为NbC粒子依附TiN粒子的形核析出提供条件,形成了更为细小和弥散分布的第二相粒子,有利于抑制道次间奥氏体的静态再结晶并有效提升热轧厚重H型钢的强韧性。Due to the limited reduction during the hot rolling of heavy hot-rolled H beam,the conventional method such as"strain induced transformation"can′t be applied to achieve the microstructure refinement of heavy hot-rolled H-beam.A new method by means of the abundant austenite grain boundaries providing the nucleation sites for fer-rite transformation has been proposed,in which a reasonable microalloying is necessary to be considered.The theo-retical analysis shows that the refinement of austenite grains before the finish rolling contributes to reducing the crit-ical strain for austenite dynamic recrystallization and then stimulating the occurrence of dynamic recrystallization.Therefore,how to restrain the austenite grain growth during the rough rolling by use of the second phase particles existed stably at high temperatures becomes one of the key issues to be considered during the microalloying of heavy hot-rolled H beam.The experimental results show that the Ti/N microalloying is conducive to the grain refinement of heavy hot-rolled H-beam due to the inhibition of the grain growth during the reheating and rough rolling.Fur-thermore,NbC particles tend to be precipitated epitaxially attaching to TiN particles,resulting in the more fined and dispersed distribution,which is beneficial to suppress the static recrystallization during passes and then improve the strength and toughness of heavy hot-rolled H-beam.

关 键 词：Nb/V/Ti微合金化 热轧H型钢 奥氏体动态再结晶 第二相粒子 超细奥氏体 

分 类 号：TG142.1[一般工业技术—材料科学与工程]