添加微量Cr元素对700MPa大梁钢氧化铁皮粉化性能的影响  

Effect of adding trace amount Cr element on the pulverization performance of scale on the surface of 700 MPa beam plate

作　　者：王畅 王林 于洋 李旭东 惠亚军 武巧玲[3] WANG Chang;WANG Lin;YU Yang;LI Xudong;HUI Yajun;WU Qiaoling(Thin Plate Research Institute,Shougang Technology Research Institute Co.,Ltd.,Beijing 100043,China;Beijing Key Laboratory of Green Recyclable Process for Iron and Steel Production Technology,Beijing 10o043,China;Shougang Qian'an Steel Company,Qian'an 064404,China)

机构地区：[1]首钢技术研究院有限公司薄板研究所,北京100043 [2]绿色可循环钢铁流程北京市重点实验室,北京100043 [3]首钢迁钢公司,河北迁安064404

出　　处：《轧钢》2024年第3期29-34,共6页Steel Rolling

摘　　要：700 MPa大梁钢生产中卷取温度和冷却速率对氧化铁皮结构及其粉化性能有重要影响,但如大范围调整卷取温度对700 MPa大梁钢的组织细化以及Ti元素析出均有影响,易造成产品力学性能和冲压性能的波动,而且卷取后冷却速率的控制手段较为有限。故从添加合金元素的角度,在保证700 MPa大梁钢力学性能的基础上,研究了通过添加微量Cr元素对700 MPa大梁钢(700L钢)氧化铁皮厚度及其粉化性能的改善效果。采用差热分析仪、扫描电镜和冷弯试验等手段,系统研究了添加质量分数0.2%Cr元素对700L钢的氧化特性、氧化铁皮生长规律及其粉化性能的影响。结果表明:添加质量分数0.2%的Cr元素后,在1 050℃以下,700L钢抗氧化性提高;在1 000℃时,700L钢等温氧化增重量降幅可达26%,氧化铁皮界面形成了元素富集层且厚度近6μm。工业生产试验表明:在热轧工艺相同条件下,添加质量分数0.2%的Cr元素后,700L热轧板表面氧化铁皮厚度由10~15μm降至6~8μm,氧化铁皮粉化脱落比例由40%降低至7%左右。The coiling temperature and cooling rate have a significant impact on the structure and pulverization performance of scale in the production of 70o MPa beam steel.However,adjusting the coiling temperature on a large scale can affect the microstructure refinement and Ti element precipitation of 700 MPa beam steel,which can easily cause fluctuations in the mechanical and stamping properties of the product,and the control methods for the cooling rate after coiling are relatively limited.Therefore,from the perspective of adding alloying elements,this article studies the improvement effect of adding trace amounts Cr element on the thickness and pulverization performance of scale on the surface of 700 MPa beam steel(700L steel)while ensuring the mechanical properties of 700 MPa beam steel.The effects of adding 0.2%Cr element on the oxidation characteristics,scale growth pattern and pulverization performance of 700L steel were systematically studied using differential thermal analysis,scanning electron microscopy,and cold bending tests.The results showed that after adding O.2%Cr element,the oxidation resistance of 700L steel increased below 1050℃.At 1000℃,the weight decreased percent of 700L steel during isothermal oxidation can reach 26%,and an element enrichment layer with a thickness of nearly 6μm is formed at the interface of the scale.Industrial production tests have shown that under the same hot rolling process conditions,the surface scale thickness of 7ooL hot-rolled plate decreases from 10-15μm to 6-8μm after adding 0.2%Cr element.The proportion of scale pulverization and peeling has decreased from 40%to about 7%.

关 键 词：氧化铁皮 CR元素 700L大梁钢 氧化铁皮粉化性能 氧化增重 元素富集 

分 类 号：TG142.1[一般工业技术—材料科学与工程]