工程科学学报，第38卷，第9期：1257-1263,2016年9月 Chinese Journal of Engineering,Vol.38,No.9:1257-1263,September 2016 D0l:10.13374/j.issn2095-9389.2016.09.009:http://journals.ustb.edu.cn 原位观察MS对非调质钢拉伸性能各向异性的影响 李梦龙12》，王福明四，李长荣》，陶素芬”，孟庆勇” 1)北京科技大学治金与生态工程学院，北京1000832)河钢集团唐钢公司技术中心，唐山063016 3)北京科技大学材料科学与工程学院，北京100083 ☒通信作者，E-mail:wangfuming(@meta.ustb.cdu.cn 摘要利用激光共聚焦扫描显微镜原位观察S质量分数为0.065%的非调质钢纵向与横向拉伸过程中MS的行为，研究 MnS形貌与分布对非调质钢各向异性的影响.原位观察表明锻后钢中存在大量长条形MnS,横向与纵向拉伸过程中MS长 度方向与拉力方向取向不同.横向拉伸过程中MS更易与基体分离产生裂纹，裂纹随MS长度方向扩展长大，最终导致基体 的断裂.MS在纵向拉伸时不易与基体分离，因此对纵向拉伸性能影响较小.钢中群聚分布的MS有利于裂纹的聚合长大， 会促进基体的断裂 关键词非调质钢：原位观察：硫化锰：拉伸性能：各向异性 分类号TF701.3 In-situ observation of MnS effect on the tensile strength anisotropy of non-quenched and tempered steel LI Meng-Hong,WANG Fu-ming,LI Chang-rong,TAO Su-fen,MENG Qing-yong" 1)School of Metallurgical and Ecological Engineering,University of Seience and Technology Beijing,Beijing 100083,China 2)Tangsteel Company Technical Center,Hesteel Group Co.,Ld.,Tangshan 063016,China 3)School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100083,China Corresponding author,E-mail:wangfuming@metall.ustb.edu.cn ABSTRACT In-situ observation of the behavior of MnS inclusions in non-quenched and tempered steel with a sulfur mass fraction of 0.065%was performed during tensile tests by using a laser confocal scanning microscope (LCSM)to investigate the effects of the morphology and distribution of MnS inclusions on the tensile property anisotropy of the steel.The result shows that there exist a large number of rod-like MnS inclusions in the forged steel,which have different orientations with the load during transverse and longitudinal tensile tests.The rod-like MnS inclusions separate much easier from the steel base during transverse tensile tests to form initial cracks, and then the cracks spread along the MnS inclusions.In this way,the cracks grow up and lead to the fracture of the steel.In contrast, the MnS inclusions have little effects on the longitudinal tensile properties because the length direction of MnS is parallel to the tensile force.MnS inclusion aggregation promotes the assembling and growth of single cracks,thus accelerating the fracture of the steel during tensile tests. KEY WORDS non-quenched and tempered steel;in-situ observation:manganese sulfide:tensile properties:anisotropy MS在一般钢中作为有害夹杂出现，但在汽车用 应用于汽车连杆、曲轴等轴类零件的加工，随我国汽车 含硫非调质钢中可以大大改善切削性能”，降低零部 行业特别是中高端汽车的快速发展非调质钢具有广阔 件机械加工的成本.非调质钢目前已广泛代替调质钢 的应用前景四，同时也对其提出更高的强韧性能要求. 收稿日期：2015-11-12 基金项目：国家自然科学基金资助项目(51174020：51374018)：国家高技术研究发展计划资助项目(2013AA031601):十三五国家重点研发 计划资助项目(2016YFB0300102)工程科学学报，第 38 卷，第 9 期: 1257--1263，2016 年 9 月 Chinese Journal of Engineering，Vol． 38，No． 9: 1257--1263，September 2016 DOI: 10． 13374 /j． issn2095--9389． 2016． 09． 009; http: / /journals． ustb． edu． cn 原位观察 MnS 对非调质钢拉伸性能各向异性的影响 李梦龙1，2) ，王福明1) ，李长荣3) ，陶素芬1) ，孟庆勇1) 1) 北京科技大学冶金与生态工程学院，北京 100083 2) 河钢集团唐钢公司技术中心，唐山 063016 3) 北京科技大学材料科学与工程学院，北京 100083  通信作者，E-mail: wangfuming@ metall． ustb． edu． cn 摘 要 利用激光共聚焦扫描显微镜原位观察 S 质量分数为 0. 065% 的非调质钢纵向与横向拉伸过程中 MnS 的行为，研究 MnS 形貌与分布对非调质钢各向异性的影响． 原位观察表明锻后钢中存在大量长条形 MnS，横向与纵向拉伸过程中 MnS 长 度方向与拉力方向取向不同． 横向拉伸过程中 MnS 更易与基体分离产生裂纹，裂纹随 MnS 长度方向扩展长大，最终导致基体 的断裂． MnS 在纵向拉伸时不易与基体分离，因此对纵向拉伸性能影响较小． 钢中群聚分布的 MnS 有利于裂纹的聚合长大， 会促进基体的断裂． 关键词 非调质钢; 原位观察; 硫化锰; 拉伸性能; 各向异性 分类号 TF701. 3 In-situ observation of MnS effect on the tensile strength anisotropy of non-quenched and tempered steel LI Meng-long1，2) ，WANG Fu-ming1)  ，LI Chang-rong3) ，TAO Su-fen1) ，MENG Qing-yong1) 1) School of Metallurgical and Ecological Engineering，University of Science and Technology Beijing，Beijing 100083，China 2) Tangsteel Company Technical Center，Hesteel Group Co． ，Ltd． ，Tangshan 063016，China 3) School of Materials Science and Engineering，University of Science and Technology Beijing，Beijing 100083，China  Corresponding author，E-mail: wangfuming@ metall． ustb． edu． cn ABSTＲACT In-situ observation of the behavior of MnS inclusions in non-quenched and tempered steel with a sulfur mass fraction of 0. 065% was performed during tensile tests by using a laser confocal scanning microscope ( LCSM) to investigate the effects of the morphology and distribution of MnS inclusions on the tensile property anisotropy of the steel． The result shows that there exist a large number of rod-like MnS inclusions in the forged steel，which have different orientations with the load during transverse and longitudinal tensile tests． The rod-like MnS inclusions separate much easier from the steel base during transverse tensile tests to form initial cracks， and then the cracks spread along the MnS inclusions． In this way，the cracks grow up and lead to the fracture of the steel． In contrast， the MnS inclusions have little effects on the longitudinal tensile properties because the length direction of MnS is parallel to the tensile force． MnS inclusion aggregation promotes the assembling and growth of single cracks，thus accelerating the fracture of the steel during tensile tests． KEY WOＲDS non-quenched and tempered steel; in-situ observation; manganese sulfide; tensile properties; anisotropy 收稿日期: 2015--11--12 基金项目: 国家自然科学基金资助项目( 51174020; 51374018) ; 国家高技术研究发展计划资助项目( 2013AA031601) ; 十三五国家重点研发 计划资助项目( 2016YFB0300102) MnS 在一般钢中作为有害夹杂出现，但在汽车用 含硫非调质钢中可以大大改善切削性能［1］，降低零部 件机械加工的成本． 非调质钢目前已广泛代替调质钢 应用于汽车连杆、曲轴等轴类零件的加工，随我国汽车 行业特别是中高端汽车的快速发展非调质钢具有广阔 的应用前景［2］，同时也对其提出更高的强韧性能要求．