石墨模具结构优化改善青铜水平连铸坯组织  

Microstructure Modification of Bronze Horizontal Continuous Casting Billet by Structure Optimization of Graphite Mold

作　　者：郑莲宝 王松伟 宋鸿武[2] 孔凡亚[2] 徐勇[2] ZHENG Lianbao;WANG Songwei;SONG Hongwu;KONG Fanya;XU Yong(College of Metallurgy and Energy,North China University of Science and Technology,Tangshan 063200;Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016)

机构地区：[1]华北理工大学冶金与能源学院,唐山063200 [2]中国科学院金属研究所,沈阳110016

出　　处：《特种铸造及有色合金》2024年第9期1218-1226,共9页Special Casting & Nonferrous Alloys

基　　金：中国科学院国际合作资助项目(172GJHZ2022054GC)。

摘　　要：锡磷青铜在水平连铸生产时,边部冷却强度较大而优先凝固,导致铸坯横向组织不均匀,并严重影响后续轧制成形和成品带材性能。提出在石墨模具表面开设空气槽结构以实现适当增加边部热阻,达到边部与芯部冷却强度一致的效果。通过有限元软件对水平连铸结晶器进行模型建立及温度场分析,采用元胞自动机法对优化前、后铸坯组织进行计算,并结合正交试验对模具表面空气槽尺寸进行优化,得到最佳空气槽尺寸,长为115 mm、宽为45 mm、深为1 mm。通过工业化试验可知,使用空气槽模具后铸坯表面结晶线弧度区减小了46 mm,铸坯横向温差减小了20.23℃,边部差异化凝固组织区间范围减小了27 mm。During horizontal continuous casting of tin-phosphor bronze,the excessive cooling at the edges results in uneven transverse microstructure of billet,thus negatively affecting subsequent rolling forming processes and properties of strip products.An air groove structure was set up on the surface of graphite mold to achieve appropriate increase in thermal resistance at the edge,ensuring similar cooling strength between edges and core of billet.An accurate model for horizontal continuous casting crystallizer was established by finite element software and temperature field analysis was conducted.The cellular automaton method was employed to compute the microstructure of billet before and after optimization,and parameters of air groove size on the mold surface were optimized by orthogonal experiments.The optimal dimensions of air groove are determined as length of 115 mm,width of 45 mm,and depth of 1 mm.Industrial testing verifies that the arc area of surface crystallization line of casting billet with air groove is reduced by 46 mm,the transverse temperature difference is reduced by 20.23℃,and the range of differentiated solidified structure at the edge is reduced by 27 mm.

关 键 词：锡磷青铜 空气槽 正交试验 横向温差 凝固组织 

分 类 号：TG113.1[金属学及工艺—物理冶金] TG146.11[金属学及工艺—金属学]