冷却速率对耐候钢中磷元素宏观偏析的影响  

Effect of cooling rate on phosphorus macrosegregation of weather resistant steel

作　　者：郭宏海[1] 宋波[1] 毛璟红[2] 赵沛 

机构地区：[1]北京科技大学冶金与生态工程学院,北京100083 [2]北京科技大学材料科学与工程学院,北京100083 [3]中国钢研科技集团公司,北京100081

出　　处：《炼钢》2010年第4期55-59,共5页Steelmaking

基　　金：国家“973”计划资助项目(2004CB619107)

摘　　要：利用氧化铝保温模、钢模、铜冷却壁水冷模来浇铸得到不同冷却速率的耐候钢铸锭试样,研究了不同冷却速率对其凝固组织及磷元素宏观偏析的影响。结果表明,加快冷却速度可以细化柱状晶和等轴晶,有效减小磷偏析。为了深入研究冷却速度对耐候钢磷偏析的影响机理,利用定向凝固设备制备了不用拉速的定向凝固试样,利用电子探针分析其糊状区,得出不同冷却速率下耐候钢试样磷元素的溶质分配系数。研究表明,提高拉速,可以细化晶粒,使糊状区变宽,并降低糊状区溶质浓度,增大耐候钢中磷元素溶质分配系数,并明显降低耐候钢中磷元素的宏观偏析。Study on the effect of various cooling rates on the solidification structure and phosphorus macrosegregation of the weather resistant steel has been made by utilizing temperature holding mould, steel mould and water cooling copper mould. Results show that accelerated cooling may refine the cylindrical crystal and equiaxed crystal and effectively diminish the macrosegregation of phosphorus at the same time. In order to further study the mechanism of effect of the cooling rate on the phosphorus macrosegregation of weather resistant steel directional solidification samples of various pulling speed are prepared by the directional solidification equipments and at the same time the mushy zone is analyzed by the electron probe. And in the end the solute distribution coefficients of phosphorus of weather resistant steel sample with different cooling rates are determined. Study shows that the grain size can be refined, the musy zone widened, the concentration of the solute in the mushy zone reduced and the solute distribution coefficient of phosphorus in the weather resistant steel enlarged. The macrosegregation of phosphorus in the weather resistant steel is prominently lowered as well.

关 键 词：耐候钢 宏观偏析 冷却速度 分配系数 磷 

分 类 号：TG142.71[一般工业技术—材料科学与工程]