炼钢连铸工艺对低合金钢特厚板Z向性能影响  

Influence of Continues Casting Process on Z Direction Properties of Low Alloy Heavy Steel Plate

作　　者：冯赞[1] 廖宏义 脱臣德 刘琴[1] 张娉 FENG Zan;LIAO Hongyi;TUO Chende;LIU Qin;ZHANG Ping(Hunan Valin Xiangtan Iron&Steel Company,Xiangtan 411101,China)

机构地区：[1]湖南华菱湘潭钢铁有限公司,湖南湘潭411101

出　　处：《金属材料与冶金工程》2021年第5期27-32,共6页Metal Materials and Metallurgy Engineering

摘　　要：本文通过对拉伸断口进行宏观分析、金相观察以及断口扫描电镜观察,发现使用连铸工艺生产厚度≥100 mm的特厚板时,由于连铸偏析会导致局部的组织异常;Nb、V偏析导致的大颗粒硬性夹杂物、S元素心部偏析导致的MnS塑性夹杂物以及心部钢水补缩不及时导致的疏松,都会在特厚板心部产生局部的缺陷,导致Z向合格率的降低。通过优化低合金钢板的成分设计、残余元素的控制、连铸工艺参数优化,能有效减少特厚板心部的各类缺陷,从而减少心部低塑性区域,提高钢板的Z向拉伸断面收缩率,实现300 mm厚连铸坯稳定生产满足Z向面缩率≥35%要求的120 mm以下低合金高强特厚板。In this paper,macroscopic analysis,metallographic observation and scanning electron microscope observation were done on tensile fracture.It is found that when heavy plates with thickness≥100 mm are produced by continuous casting process,the segregation of continuous casting will lead to local abnormal structure.The large particle hard inclusion caused by Nb and V segregation,MnS plastic inclusion resulted from center segregation of S element and porosity brought about by delayed hot steel shrinking will all create local defect in the center of heavy plates,which will reduce qualification rate of Z direction properties.By optimizing the composition design of low alloy steel plate,controlling the residual elements and optimizing the continuous casting process parameters,all kinds of defects in the center of heavy plates can be effectively reduced,so as to reduce the low plastic area in the center and improve the Z-direction tensile area reduction of steel plate.Thus,stable production of 300 mm thick continuous casting slab are realized,and the requirements of Z-direction area reduction of≥35%for low alloy high strength heavy plate below 120 mm thick are satisfied.

关 键 词：低合金高强度钢 特厚板 Z向性能 

分 类 号：TG113.25[金属学及工艺—物理冶金]