Flash butt welding process and microstructure controlling of 380CL wheel steel with micro Ti treatment
-
摘要: 为解决轮辋闪光对焊(FBW)后微裂纹率和炸裂率偏高的问题，选取6.75 mm厚380CL车轮钢为研究对象，通过研究一元化闪光对焊参数对接头硬度的影响规律，建立闪光对焊温度场控制机制. 通过Ti微合金化技术思路进一步降低380CL闪光对焊焊缝的硬化倾向. 结果表明，为保证380CL闪光对焊后的成材率，需采取温度梯度较大的焊接规范，配合合理的顶锻量，从而获得最优的焊接接头. 在烧化量19 mm，钳口距离36 mm，烧化速度1.2 mm/s，带点顶锻时间0.5 s，顶锻量7 mm的闪光对焊参数下，6.75 mm厚380CL车轮钢可获得最低的硬度值140HV2. 对微Ti处理的380CL车轮钢进行了焊接热模拟，在1 000 ℃以上时的顶锻变形抗力降低，组织晶粒细化，显著降低了380CL闪光对焊后微裂纹率和炸裂率. 以上研究具备向高强度轮辋用钢的闪光对焊做进一步推广和应用示范.Abstract: In order to solve the problem of high micro-cracking rate and bursting rate after rim flash butt welding (FBW), the 380CL wheel steel with thickness of 6.75 mm is taken as the research object. By studying the influence of the unified flash butt welding parameters on the joint hardness, the control mechanism of the flash butt welding temperature field is established in this paper. The hardening tendency of the 380CL after FBW is further reduced by the Ti microalloying technology. It’s shown that in order to ensure the well-done production rate after flash butt welding of 380CL, it is necessary to adopt a welding specification with a large temperature gradient and a reasonable forging amount to obtain an optimal welded joint. Under the FBW parameters of the burnt amount of 19 mm, the jaw distance of 36 mm, the burning rate of 1.2 mm/s, the point upset forging time of 0.5 s, and the upset forging of 7 mm, the 380CL wheel steel with thickness of 6.75 mm can obtain the lowest hardness value of 140HV2. The welding heat simulation of the micro-Ti treated 380CL wheel steel was carried out. The deformation resistance of the upset forging at 1 000 °C or higher was reduced, and the grain refinement of the microstructure was remarkably reduced, which significantly reduced the micro-cracking rate and the burst rate after FBW of 380CL. The researches above have been further promoted and applied demonstration of FBW to high-strength rim steel.
-
Keywords:
- Ti microalloying /
- wheel steel /
- flash butt welding /
- hardness /
- thermal simulation
-
-
![]()
图 1 轮辋闪光焊后焊缝开裂
Figure 1. Crack cracking after rim flash welding. (a) flaring crack; (b) roll forming microcracks; (c) expansion crack
![]()
图 2 闪光对焊参数对接头硬度的变化关系
Figure 2. Relationship between flash butt welding parameters. (a) burnt amount; (b) chucking pitch; (c) burning speed; (d) power-on squeeze time; (e) extrusion amount
![]()
图 5 不同烧化速度闪光结束瞬间温度场分布
Figure 5. Temperature field distribution at the end of flashing with different burning rates. (a) burning speed of 0.9 mm/s; (b) burning speed of 1.0 mm/s; (c) burning speed of 1.1 mm/s; (d) burning speed of 1.2 mm/s
![]()
图 7 不同温度下顶锻量与顶锻压强的关系
Figure 7. Relationship between upset forging and forging pressure at different temperatures. (a) 1 100 °C; (b) 1 000 °C; (c) 900 °C; (d) 800 °C
![]()
图 8 两种成分不同温度顶锻后金相组织
Figure 8. Microstructures after forging with two components at different temperatures. (a) with original base material under 800 ℃; (b) with original base material under 1 100 ℃; (c) with base material with micro Ti treatment under 800 ℃; (d) with base material with micro Ti treatment under1 100 ℃
![]()
图 9 380CL熔合线及母材的IPF图
Figure 9. IPF diagrams of 380CL fusion line and base metal. (a) original base material; (b) flash welding fusion line with original composition; (c) base material with micro Ti treatment; (d) flash welding fusion line of base material with micro Ti treatment
表 1 380CL化学成分(质量分数，％)
Table 1 Chemical composition of 380CL
C Si Mn P S Al Ti 0.092 0.011 0.92 0.010 0.008 0.033 0.0009 
下载: 导出CSV
表 2 380CL车轮钢横向拉伸力学性能
Table 2 Transverse tensile mechanical properties of 380CL wheel steel
厚度 t / mm 屈服强度 ReL / MPa 抗拉强度 Rm / MPa 比例伸长率 A50 (%) 最大力总伸长率 Agt (%) 屈服点伸长率 Ae (%) 6.0 ~ 7.3 301 ~ 310 400 ~ 430 40 ~ 45 15 ~ 20 2 ~ 4
下载: 导出CSV
表 3 微Ti处理前后380CL车轮钢的化学成分(质量分数，％)
Table 3 Chemical composition of 380CL wheel steel before and after micro-Ti treatment
试样 C Si Mn P S Al Ti 原成分 0.092 0.011 0.92 0.010 0.008 0.033 0.0009 微Ti处理 0.066 0.01 1.04 0.012 0.003 0.034 0.012
下载: 导出CSV
表 4 闪光对焊工艺参数
Table 4 Process parameters of flash butt welding
钳口距离
d / mm烧化量
b / mm烧化速度
v / (mm·s−1)带电顶锻时间
t / s顶锻量
e / mm36 19 1.2 0.5 7
下载: 导出CSV
表 5 闪光焊接头拉伸性能对比
Table 5 Comparison of tensile properties of FBW joints
试样 规格 屈服强度 ReL / MPa 抗拉强度 Rm / MPa 比例伸长率 A20 (%) 最大力总伸长率 Agt (%) 屈服点伸长率 Ae (%) 原成分 光滑试样 430.8 476.2 34.9 1.5 1.3 缺口试样 389 470 21 18.5 6.9 微Ti处理 光滑试样 315.6 411.8 38 37.9 14.9 缺口试样 312 399 29.5 32.6 14.8
下载: 导出CSV
表 6 微Ti处理的380CL应用效果
Table 6 Application effect of 380CL wheel steel with micro Ti treatment
用户(产线) 材料 裂纹率 报废率 客户要求 微裂纹率 报废率 A 原380CL 5.6% 0.3% < 3% < 0.7% 微钛380CL 1.3% 0.1% B 原380CL 25% 1.8% < 3% < 0.3% 微钛380CL 1% 0.2% C 原380CL 20% 4% < 3% < 0.7% 微钛380CL 0.8% 0.1% D 原380CL 80% 16.7% < 10% < 0.7% 微钛380CL 1 % 0.3% E 原380CL 80% 10% < 10% < 0.7% 微钛380CL 1.5 % 0.4%
下载: 导出CSV
-
[1] 中国汽车工程学会. 节能与新能源汽车技术路线图[M]. 北京: 机械工业出版社, 2016 [2] 张大伟, 杜林秀, 肖宝亮, 等. 乘用车轮辐用600 MPa级热轧双相钢失效原因分析[J]. 金属热处理, 2018, 43(7): 224 − 228. Zhang Dawei, Du Linxiu, Xiao Baoliang, et al. Failure analysis of 600 MPa hot rolled dual phase steel for passenger car wheel spoke[J]. Heat Treatment of Metals, 2018, 43(7): 224 − 228.
[3] 马鸣图, Shi M F. 先进的高强度钢及其在汽车工业中的应用[J]. 钢铁, 2004(7): 68 − 72. doi: 10.3321/j.issn:0449-749X.2004.07.018 Ma Mingtu, Shi M F. Advanced high strength steel and its applications in automobile industry[J]. Iron and Steel, 2004(7): 68 − 72. doi: 10.3321/j.issn:0449-749X.2004.07.018
[4] 康永林, 邝霜, 尹显东, 等. 汽车用双相钢板的开发与研究进展[J]. 汽车工艺与材料, 2006(5): 1 − 5. doi: 10.3969/j.issn.1003-8817.2006.05.001 Kang Yonglin, Kuang Shuang, Yin Xiandong, et al. Research on progress and development of dual phase sheet for aytomobiles[J]. Technology and Material, 2006(5): 1 − 5. doi: 10.3969/j.issn.1003-8817.2006.05.001
[5] Gong Y H, Gong M Y, Sun D Q. Study on microstructures and properties of preheated flash butt welded SW400 steel joints[J]. China Welding, 2018, 27(3): 42 − 52.
[6] 王利, 杨雄飞, 陆匠心. 汽车轻量化用高强度钢板的发展[J]. 钢铁, 2006(9): 1 − 8. doi: 10.3321/j.issn:0449-749X.2006.09.001 Wang Li, Yang Xiongfei, Lu Jiangxin. Development of high strength steel sheets for lightweight automobile[J]. Iron and Steel, 2006(9): 1 − 8. doi: 10.3321/j.issn:0449-749X.2006.09.001
[7] 徐志欣. 590 MPa级高强钢轮辋接头组织性能与失效分析[D]. 厦门: 华侨大学, 2017. [8] 郗晨瑶. RS590CL钢闪光对焊接头微观组织及力学性能的研究[D]. 吉林: 吉林大学, 2016. [9] 张楠, 田志凌, 张书彦, 等. Q700D热影响粗晶区疲劳寿命与小裂纹扩展分析[J]. 钢铁研究学报, 2019, 31(8): 741 − 747. Zhang Nan, Tian Zhiling, Zhang Shuyan, et al. Prediction of fatigue life and behavior analysis of small crack[J]. Journal of Iron and Steel Research, 2019, 31(8): 741 − 747.
[10] 张楠, 董现春, 潘辉, 等. 高Ti-Nb系高强钢焊接接头回火前后的力学行为[J]. 焊接学报, 2015, 36(5): 93 − 98. Zhang Nan, Dong Xianchun, Pan Hui, et al. Mechanical behavior of welded joint of a high Ti-Nb content microalloyed high-strength steel before and after drawing temper treatment[J]. Transactions of the China Welding Institution, 2015, 36(5): 93 − 98.
[11] 董现春, 张楠, 陈延清, 等. 800 MPa级钛铌析出强化高强钢焊接接头的组织与力学性能[J]. 机械工程材料, 2014, 38(11): 21 − 25. Dong Xianchun, Zhang Nan, Chen Yanqing, et al. Microstructure and mechanical properties of welded joints of 800 MPa high strength steels with Ti and Nb precipitation strengthening[J]. Materials for Mechanical Engineering, 2014, 38(11): 21 − 25.
[12] 张楠, 董现春, 徐晓宁, 等. Ti-Nb微合金化高强钢的焊接接头组织和性能[J]. 材料热处理学报, 2014, 35(6): 115 − 120. Zhang Nan, Dong Xianchun, Xu Xiaoning, et al. Microstructure and property of welding joint with Ti-Nb microalloyed high-strength steel[J]. Transactions of Materials and Heat Treatment, 2014, 35(6): 115 − 120.
[13] 董现春, 张楠, 陈延清, 等. 高Ti, Nb析出强化高强钢接头强度及焊接热影响区软化行为分析[J]. 焊接学报, 2012, 33(11): 72 − 76. Dong Xianchun, Zhang Nan, Chen Yanqing, et al. The welded joint strength and analysis for HAZ softening behavior of high Ti and Nb precipitation strengthing high strength steel[J]. Transactions of the China Welding Institution, 2012, 33(11): 72 − 76.
[14] 张楠, 董现春, 张熹, 等. 钛微合金化SQ700MCD高强钢粗晶热影响区软化的原因[J]. 机械工程材料, 2012, 36(4): 88 − 92. Zhang Nan, Dong Xianchun, Zhang Xi, et al. The softening analysis of CGHAZ in Ti microalloyed SQ700MCD steel[J]. Materials for Mechanical Engineering, 2012, 36(4): 88 − 92.
[15] 张楠, 田志凌, 张书彦, 等. 700 MPa微合金高强钢焊接软化机理及解决方案[J]. 钢铁研究学报, 2019, 31(3): 318 − 326. Zhang Nan, Tian Zzhiling, Zhang Shuyan, et al. Mechanism and solution of welding softening for 700 MPa microalloyed high strength steel[J]. Journal of Iron and Steel Research, 2019, 31(3): 318 − 326.
[16] 雍岐龙. 钢铁材料中的第二相[M]. 北京: 冶金工业出版社, 2006. [17] Pereloma E V, Crawford B R, Hodgson P D. Strain-induced precipitation behaviour in hot rolled strip steel[J]. Materials Science and Engineering, 2000, 299A(1-2): 27.
[18] 付魁军, 高铭泽, 冷雪松, 等. TiNb钢焊接热影响区微观组织与冲击性能演变规律[J]. 焊接学报, 2019, 40(5): 36 − 41. Fu Kuijun, Gao Mingze, Leng Xuesong, et al. Evolution of microstructure and impact property in welding HAZ of TiNb steel[J]. Transactions of the China Welding Institution, 2019, 40(5): 36 − 41.
[19] 缪成亮, 刘振伟, 郭晖, 等. Nb含量和热输入量对X80管线钢焊接粗晶区的影响[J]. 材料热处理学报, 2012, 33(1): 99 − 105. Miao Chengliang, Liu Zhenwei, Gou Hui, et al. Effect of Nb content and heat input on coarse-grained welding heat affected zone of X80 pipeline steels[J]. Transactions of Materials and Heat Treatment, 2012, 33(1): 99 − 105.
[20] 张楠, 陈延清, 徐晓宁, 等. X80管线钢Cu-Ni含量及热输入对CGHAZ冲击离散性的影响[J]. 焊接学报, 2016, 37(9): 119 − 124. Zhang Nan, Chen Yanqing, Xu Xiaoning, et al. Effect of Cu-Ni components in X80 pipeline and heat input on discretization of toughness in CGHAZ[J]. Transactions of the China Welding Institution, 2016, 37(9): 119 − 124.
计量
- 文章访问数: 501
- HTML全文浏览量: 9
- PDF下载量: 25
