|
|
|
| Effect of annealing on dendritic segregation and elemental diffusion of gear steel billet |
| ZHAO Yi-na1， CHEN Yin-li2， YU Wei1， WANG Yun-long2， FAN Wen-sheng2 |
| （1. Engineering Technology Institute， University of Science and Technology Beijing， Beijing 100083， China； 2. 2011 Collaborative Innovation Center for Common Steel Technologies， University of Science and Technology Beijing， Beijing 100083， China） |
|
|
|
|
Abstract In order to study the effects of annealing process on the dendritic morphology of 20CrMnTi gear steel slab，the distribution of alloying elements （C，Si，Cr and Mn） and its diffusion，the optical microscope （OM） was used to shape the dendrites before and after annealing. The appearance was compared and the distribution of the elements was quantitatively analyzed using an electron probe （EPMA），and the simulation was performed using the Dictra module in the Thermo-Calc software. The results showed that the dendritic morphology of the 20CrMnTi gear steel slab was more complete and clear，and the secondary dendrite spacing in the slab after annealing was measured to be 55 μm. The C element in the slab had an upward slope，the segregation coefficient became larger，the variation of the segregation coefficient was ?kC＝0.666. The Si element had a slight uphill diffusion，the variation of the segregation coefficient was ?kSi=0.041 5. The Mn element diffusion was more uniform，and the variation coefficient of the segregation coefficient was ΔkMn＝－0.141. The Cr element also diffused more uniformly and the variation coefficient of the segregation coefficient was ΔkCr＝－0.106. The simulation results showed that under the annealing condition of slab temperature of 680 ℃ and holding time of 2 h，C atoms were up-slope and diffuse，resulting in segregation. Si，Cr and Mn atoms had no obvious diffusion changes.
|
|
Received: 19 June 2018
Published: 15 February 2019
|
|
|
|
| [1]纪元，闵文峰，李鹏善，刘华松，张家泉.钢中带状组织及其研究现状[J]., 2016, 26(04):1-9 [2]纪元, 闵云峰, 李鹏善, 刘华松, 张家泉.钢中带状组织及其研究现状[J].中国冶金, 2016, 26(04):1-9 [3]张迎晖, 赖泓州, 赵鸿金.钢中带状组织的研究现状[J].轧钢, 2014, 31(03):45-47 [4]王芳, 袁书强, 田雨江, 高永亮, 陈炯, 刘峰涛, 周春华, 胡俊.带状组织减轻或消除工艺研究现状[J].热加工工艺, 2013, 42(05):52-54 [5]Sakir Bor A.Effecct of Pearlite Banding on Mechanical Properties of Hot-rolled Steel Plates[J].ISIJ International, 1991, 31(12):1445- [6]Shanmugam P, Pathk S D.Some Studies on the Impact Behavior of Banded Microalloyed Steel[J].Engineering Fracture Mechanics, 1996, 53(6):991- [7] 柳得橹, 邵伟然, 孙贤文, 霍向东, 毛新平, 李烈军.钢的表面带状组织及其引起的冷弯裂纹[J].北京科技大学学报, 2005(01):40-44. [8]张延玲, 刘海英, 阮小江, 李国忠, 白李国, 王福明.中低碳齿轮钢中合金元素的偏析行为及其对带状组织的影响[J].北京科技大学学报, 2009, 31(S1):199-206 [9] 许庆太, 李吉东, 孙中强.枝晶腐蚀低倍检验在连铸生产中的应用[J]. 物理测试, 2011, (06):22-27. [10] 柳洋波.一种齿轮钢连铸坯枝晶显示方法[A]. 中国金属学会（The Chinese Society for Metals）、宝钢集团有限公司（Baosteel Group Coporation）.“第十届中国钢铁年会”暨“第六届宝钢学术年会”论文集[C].中国金属学会（The Chinese Society for Metals）、宝钢集团有限公司（Baosteel Group Coporation）, 2015:5. [11] 王新华.钢铁冶金-炼钢学[M]. 北京：高等教育出版社, 2007: 305-306. [12]Vannier I, Combeau H, Lesoult G.Numerical model for prediction of the final segregation pattern of bearing steel ingots[J].Materials Science and Engineering: A, 1993, 173(1-2):317-321 |
| [1] |
LI Yao, CHENG Guo-guang, LU Jin-long, SUN Jun, HUANG Yu. Effect of TiN precipitation on hardenability in 20CrMnTi gear steel[J]. Iron and Steel, 2021, 56(1): 75-84. |
| [2] |
LI Chen-guang, BAO Han-sheng, LI Li, BAI Yin, ZHANG Wei, ZHAO Ji-qing. Steam oxidation behavior of 2.25Cr-1Mo steel for nuclear power[J]. Iron and Steel, 2021, 56(1): 91-96. |
| [3] |
CHEN Wen, WANG Xin, LEI Ying, LI Yu, HE Si-qi, LIAO Zhen-hong. Isothermal reduction kinetics of high-phosphorus iron ore carbon-containing pellets[J]. Iron and Steel, 2020, 55(9): 11-15. |
| [4] |
WANG Yu, ZOU Chong, LI Jian-yun, LIU Zhi-wei, ZHAO Jun-xue, WANG Wei-an. Combustion performance of blast furnace pulverized coal mixed with metallurgical sludge[J]. Iron and Steel, 2020, 55(8): 115-122. |
| [5] |
TIAN Jun1,WANG De-yong1,QU Tian-peng1,HOU Dong1,GE Wen-ying2,LIU Bing2. MnS precipitation and growth during solidification of nonquenched and tempered steel[J]. JOURNAL OF IRON AND STEEL RESEARCH , 2020, 32(8): 740-745. |
| [6] |
CHENG Lei, SUN Bin, DU Chong-yang. Oxidation behavior of Fe-Cr steel in air[J]. Iron and Steel, 2020, 55(7): 120-126. |
|
|
|
|
2019, Vol. 54 
