工程科学学报，第39卷，第6期：846853,2017年6月 Chinese Journal of Engineering,Vol.39,No.6:846-853,June 2017 DOI:10.13374/j.issn2095-9389.2017.06.005:http://journals.ustb.edu.cn 钛稀土复合处理对CMn钢粗晶热影响区组织及韧性 的影响 张圣华12，宋波2)，宋明明》，高启瑞2 1)北京科技大学治金与生态工程学院，北京1000832)北京科技大学钢铁治金新技术国家重点实验室，北京100083 3)武汉科技大学耐火材料与治金国家重点实验室，武汉430081 ☒通信作者，E-mail:songbo@metall.ustb.cdu.cn 摘要利用Gleeble--一l50OD热模拟机进行焊接热影响区热循环模拟实验，研究了在焊接热输入为65k·cm时稀土单独处 理和钛稀土复合处理对C一M钢粗晶热影响区组织及冲击韧性的影响，并利用扫描电镜观察和分析了实验钢中的夹杂物和 冲击断口形貌，利用光镜观察了热循环模拟后实验钢中的微观组织.实验结果表明：稀土单独处理和钛稀土复合处理的试样 微观组织分别主要是晶界铁素体+块状铁素体+针状铁素体和晶界铁素体+晶内针状铁素体.经稀土单独处理的试样中夹 杂物为La,O,S+锰铝硅酸盐+MnS复合夹杂：钛稀土复合处理的试样中的夹杂主要是La2O,S+TiO,+锰铝硅酸盐+MnS复 合夹杂.钛稀土复合处理钢中的复合夹杂更细小，有利于形成细小的晶内针状铁素体.钛稀土复合处理极大地改善了实验钢 的焊接热影响区低温冲击韧性，比稀土单独处理对试样的冲击性能提升效果更好 关键词碳一锰钢：粗晶热影响区：针状铁素体：显微组织：冲击韧性 分类号TG142.1 Influence of Ti-rare earth addition on microstructure and toughness of coarse grain heat-affected zone in C-Mn steel ZHANG Sheng-hua,SONG Bo,SONG Ming-ming,GAO Qi-rui) 1)School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing,Beijing 100083,China 2)State Key Laboratory of Advanced Metallurgy,University of Science and Technology Beijing,Beijing 100083,China 3)State Key Laboratory for Refractories and Metallurgy,Wuhan University of Science and Technology,Wuhan 430081,China Corresponding author,E-mail:songbo@metall.ustb.edu.cn ABSTRACT The influences of rare earth (RE)and Ti-RE complex treatment on the microstructures and toughness in the coarse grain heat-affected zone (CGHAZ)of C-Mn steel were investigated using a Gleeble-1500D thermal simulator with input heat energy of 65 kJcm.The inclusions and impact fracture morphology were observed and analyzed by scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX),and the microstructure was characterized using an optical microscope (OM).The results show that the microstructures in the CGHAZs of RE-and Ti-RE-treated samples are mainly grain boundary ferrite (GBF)+polygonal fer- rite (PF)+intragranular acicular ferrite (IAF)and grain boundary ferrite intragranular acicular ferrite,respectively.Inclusions in the RE-treated specimen are La,O,S Mn-Al-Si-0 MnS,while those in the Ti-RE-treated specimen are La,O,S TiO, Mn-Al-Si-0 MnS.The complex inclusions in Ti-RE-treated steel are smaller than those in RE-treated steel,and the size of IAF in Ti-RE-treated steel is smaller.The impact properties of the CGHAZ in Ti-RE-treated C-Mn steel is improved significantly,and the material is tougher than RE-treated steel. 收稿日期：2016-10-10 基金项目：国家自然科学基金资助项目(51274269)工程科学学报，第 39 卷，第 6 期: 846--853，2017 年 6 月 Chinese Journal of Engineering，Vol． 39，No． 6: 846--853，June 2017 DOI: 10． 13374 /j． issn2095--9389． 2017． 06． 005; http: / /journals． ustb． edu． cn 钛稀土复合处理对 C--Mn 钢粗晶热影响区组织及韧性 的影响 张圣华1，2) ，宋 波1，2) ，宋明明3) ，高启瑞1，2) 1) 北京科技大学冶金与生态工程学院，北京 100083 2) 北京科技大学钢铁冶金新技术国家重点实验室，北京 100083 3) 武汉科技大学耐火材料与冶金国家重点实验室，武汉 430081 通信作者，E-mail: songbo@ metall． ustb． edu． cn 收稿日期: 2016--10--10 基金项目: 国家自然科学基金资助项目( 51274269) 摘 要 利用 Gleeble--1500D 热模拟机进行焊接热影响区热循环模拟实验，研究了在焊接热输入为 65 kJ·cm － 1时稀土单独处 理和钛稀土复合处理对 C--Mn 钢粗晶热影响区组织及冲击韧性的影响，并利用扫描电镜观察和分析了实验钢中的夹杂物和 冲击断口形貌，利用光镜观察了热循环模拟后实验钢中的微观组织． 实验结果表明: 稀土单独处理和钛稀土复合处理的试样 微观组织分别主要是晶界铁素体 + 块状铁素体 + 针状铁素体和晶界铁素体 + 晶内针状铁素体． 经稀土单独处理的试样中夹 杂物为 La2O2 S + 锰铝硅酸盐 + MnS 复合夹杂; 钛稀土复合处理的试样中的夹杂主要是 La2O2 S + TiOx + 锰铝硅酸盐 + MnS 复 合夹杂． 钛稀土复合处理钢中的复合夹杂更细小，有利于形成细小的晶内针状铁素体． 钛稀土复合处理极大地改善了实验钢 的焊接热影响区低温冲击韧性，比稀土单独处理对试样的冲击性能提升效果更好． 关键词 碳--锰钢; 粗晶热影响区; 针状铁素体; 显微组织; 冲击韧性 分类号 TG142. 1 Influence of Ti-rare earth addition on microstructure and toughness of coarse grain heat-affected zone in C--Mn steel ZHANG Sheng-hua1，2) ，SONG Bo1，2)  ，SONG Ming-ming3) ，GAO Qi-rui1，2) 1) School of Metallurgical and Ecological Engineering，University of Science and Technology Beijing，Beijing 100083，China 2) State Key Laboratory of Advanced Metallurgy，University of Science and Technology Beijing，Beijing 100083，China 3) State Key Laboratory for Ｒefractories and Metallurgy，Wuhan University of Science and Technology，Wuhan 430081，China Corresponding author，E-mail: songbo@ metall． ustb． edu． cn ABSTＲACT The influences of rare earth ( ＲE) and Ti--ＲE complex treatment on the microstructures and toughness in the coarse grain heat-affected zone ( CGHAZ) of C--Mn steel were investigated using a Gleeble--1500D thermal simulator with input heat energy of 65 kJ·cm － 1 ． The inclusions and impact fracture morphology were observed and analyzed by scanning electron microscopy ( SEM) and energy-dispersive X-ray ( EDX) ，and the microstructure was characterized using an optical microscope ( OM) ． The results show that the microstructures in the CGHAZs of ＲE--and Ti--ＲE--treated samples are mainly grain boundary ferrite ( GBF) + polygonal fer￾rite ( PF) + intragranular acicular ferrite ( IAF) and grain boundary ferrite + intragranular acicular ferrite，respectively． Inclusions in the ＲE-treated specimen are La2O2 S + Mn--Al--Si--O + MnS，while those in the Ti--ＲE--treated specimen are La2O2 S + TiOx + Mn--Al--Si--O + MnS． The complex inclusions in Ti--ＲE--treated steel are smaller than those in ＲE-treated steel，and the size of IAF in Ti--ＲE--treated steel is smaller． The impact properties of the CGHAZ in Ti--ＲE--treated C--Mn steel is improved significantly，and the material is tougher than ＲE--treated steel．