冷却温度对AH36钢连铸坯热延展性的影响  

Effect of cooling temperature on thermal ductility of AH36 steel continuous casting slab

作　　者：付振坡 杨军[1] 操瑞宏[2] 李广生[3] 邹德宁[1] 丁畅越 

机构地区：[1]西安建筑科技大学冶金工程学院,陕西西安710055 [2]新余钢铁集团有限公司,江西新余338001 [3]西安建筑科技大学附中物理组,陕西西安710055

出　　处：《钢铁研究学报》2016年第9期66-70,共5页Journal of Iron and Steel Research

基　　金：国家自然科学基金资助项目(U1460104);西安交通大学金属材料强度国家重点实验室开放课题基金资助项目(20131314)

摘　　要：连铸坯角部横向裂纹是连续铸钢过程中经常出现的缺陷,直接影响钢材质量和生产成本。以AH36钢为研究对象,采用Gleeble-3800热模拟机模拟连铸坯冷却制度对连铸坯的影响。借助金相显微镜对断口微观组织进行分析表征,研究不同冷却温度下试样的热延展性,明确冷却温度对连铸坯角部横裂纹的影响。结果表明:以10℃/s的冷速冷却至650℃后,回温至Ac3温度以上随后再缓慢冷却至825℃时的试样断面收缩率为67.02%,并且微观组织均匀,晶粒细小。热循环冷却制度能够有效提高连铸坯表面热延展性,降低裂纹敏感性,消除角部裂纹的产生。Slab transverse corner crack is a common defect in continuous casting process, It directly affects the qu- ality of steel and the cost of production. Taking the AH36 steel as the research object, the effect of cooling system on continuous casting billet was studied by Gleeble-3800 thermal simulation machine. By using the optical micros- copy, fracture microstructure characterization was represented to study the hot ductility of the samples at different cooling temperatures and to define the effect of cooling rate on the transverse corner cracks. The results show that after the samples are cooled to 650 ℃ at 10 ℃/s, then temperature back to above At3 then slowly cooled to the temperature of 825 ℃, the reduction of area of the sample is 67.02% and the microstructure is uniform with fine grain. Thermal cycling cooling system can effectively improve hot ductility on the the surface of continuous casting billet, reduce crack sensitivity, and eliminate the corner cracks.

关 键 词：冷却温度 角部横裂纹 热延展性 热模拟 

分 类 号：TF77[冶金工程—钢铁冶金]