Transactions of Materials and Heat Treatment

Title：Hot forming process on automobile rear beam with variable strength

Authors： Zhou Jie Tan Shunqiang Chen Yejun Li Min

Unit： Chongqing University Chongqing Chang′an Ford Automobile Co. Ltd. Chongqing BND Push Auto. Parts Co. Ltd.

KeyWords： variable strength rear beam hot forming differential cooling hard zone soft zone

ClassificationCode：TP319.56

year,vol(issue):pagenumber：2019,44(11):32-38

Abstract：

For automobile rear beam parts with variable strength, the production process of rear beam parts was optimized by the hot forming process of overall heating of sheet metal and die differential cooling sheet. Compared to the hot forming process of equal-strength rear beam parts, the variable-strength hot forming process added a heating system in the soft zone, reduced the cooling rate in the soft zone of the part, achieved differential cooling in the hard and soft zones of the part, and finally obtained the rear beam parts with variable strength. Firstly, the die was designed based on the variable strength characteristics and structural characteristics of parts, and the distributions of temperature, hardness and martensitic phase content in the hard and soft zones of the whole part after forming were simulated numerically by the hot forming process. Then, the forming process parameters of rear beam parts were optimized by numerical simulation, and the optimized process parameters were adopt to guide the actual production of parts. The yield strength, tensile strength, elongation, hardness，thinning ratio and microstructure in the hard and soft zones of the trial parts were tested and analyzed. The results show that the rear beam parts with variable strength meet the design requirements.

Funds：

周杰(1965-),男，博士，教授，E-mail：zhoujie@cqu.edu.cn；通讯作者：谈顺强（1980-），男，硕士，工程师，E-mail：tanshunqiang@126.com

Reference：

[1]Merklein M, Johannes M, Lechner M, et al. A review on tailored blanks-Production, applications and evaluation[J]. Journal of Materials Processing Technology, 2014, 214(2):151-164.
[2]Mori K, Okuda Y. Tailor die quenching in hot stamping for producing ultra-high strength steel formed parts having strength distribution[J]. CIRP Annals-Manufacturing Technology, 2010, 59(1): 291-294.
[3]Lodeiro P, Siu Ming K, Jonatan Torres P, et al. Novel Fe loaded activated carbons with tailored properties for As(V) removal: Adsorption study correlated with carbon surface chemistry[J]. Chemical Engineering Journal, 2013, 215-216: 105-112.
[4]George R, Bardelcik A, Worswick M J. Hot forming of boron steels using heated and cooled tooling for tailored properties[J]. Journal of Materials Processing Technology, 2012, 212(11): 2386-2399.
[5]Karbasian H, Tekkaya A E. A review on hot stamping[J]. Journal of Materials Processing Technology, 2010, 210(15): 2103-2118.
[6]Merklein M, Wieland M, Lechner M, et al. Hot stamping of boron steel sheets with tailored properties: A review[J]. Journal of Materials Processing Technology, 2016, 228: 11-24.
[7]Sthr T, Lechler J, Merklein M. Investigations on different strategies for influencing the microstructural properties with respect to partial hot stamping[A]. Proceedings of the 2nd International Conference Hot sheet Metal Forming of High-performance steel-CHS2 [C].Auerbach,Germany,2009.
[8]Windmann M, Rttger A， Theisen W. Phase formation at the interface between a boron alloyed steel substrate and an Al-rich coating[J]. Surface & Coatings Technology, 2013, 226(14): 130-139.
[9]谭方培. 高强钢热冲压成形中的相变模型及应用研究[D]哈尔滨：哈尔滨工业大学，2016.
Tan F C. Research and Application on Phase Transformation Model of High Strength Steel in Hot Stamping[D]. Harbin: Harbin Institute of Technology, 2016.
[10]喻苗. 高强钢变强度成形的综合目标实现方法研究[D].武汉：华中科技大学, 2014.
Yu M. Research of the Implement Method for the Comprehensive Target of HSS Tailored Tempering[D]. Wuhan: Huazhong University of Science & Technology, 2014.
[11]孙喜龙,王登峰，卢放，等. 基于提高轿车后面抗撞性能的后纵梁结构优化[J]. 吉林大学学报: 工学版, 2011, 44(S2): 87-91.
Sun X L, Wang D F, Lu F, et al. Structural optimization of rear longeron based on the improving the rear crashworthness[J]. Journal of Jilin University: Engineering and Technology Edition, 2011, 44(S2): 87-91.
[12]Merklein M, Lechler J. Investigation of the thermo-mechanical properties of hot stamping steels[J]. Journal of Materials Processing Technology, 2006, 177(1-3): 452-455.
[13]盈亮. 高强度钢热冲压关键工艺试验研究与应用[D]. 大连：大连理工大学，2013.
Ying L. Research and Application on Key Process Experiment of High Strength Steel for Hot Forming[D]. Dalian: Dalian University of Technology,2013.
[14]Naderi M, Durrenberger L, Molinari A, et al. Constitutive relationships for 22MnB5 boron steel deformed isothermally at high temperatures[J]. Materials Science & Engineering A, 2008, 478(1): 130-139.
[15]Aranda L G, Chastel Y, Fernandez Pascual J, et al. Experiments and simulation of hot stamping of quenchable steels[J]. Advance Technology of Plasticity,2002,2:1135-1140.

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