Transactions of Materials and Heat Treatment

Title：Influence of die temperature on transition zone of hot stamping parts with variable strength for automotive B-pillar

Authors： Huang Chaoqun

Unit： Chongqing Technology and Business Institute

KeyWords： die temperature hot stamping process with variable strength automobile B-pillar transition zone Autoform

ClassificationCode：TG306

year,vol(issue):pagenumber：2019,44(7):52-57

Abstract：

For the automobile B-pillar, the hot stamping process scheme with variable strength of upper die-upper press plate-blank holder-lower die was designed, and the hot stamping process of automobile B-pillar with variable strength was analyzed and optimized by the hot stamping module of software Autoform. Based on the numerical simulation scheme, the influences of die temperature in the cold and hot sections on the transition zone position and width of part were investigated by taking the martensite content on the both sides of boundary between hard and soft areas as reference. During the hot stamping process with variable strength, the die temperature in the hot section becomes the main factor influencing the transition zone position and width of part due to the temperature in the soft area of part decreasing with the heat loss easily. With the decreasing of die temperature in the hot section, the position of transition zone shiftes to the soft zone of part, and the width of transition zone increases. When the die temperature in the hot section is 550 ℃, the shifting amount and the width of transition zone are up to minimum about 0.5-1 mm and 17.8-18.3 mm, respectively.

Funds：

重庆市教育委员会科学技术研究资助项目（KJ1603809）

黄超群(1981-),女,硕士,副教授，E-mail：hcq_ctbi@163.com

Reference：

[1]游国忠, 陈晓东, 程勇, 等. 轿车B柱的优化及对侧面碰撞安全性的影响[J]. 汽车工程, 2006, 28(11):972-975.

You G Z, Chen X D, Cheng Y, et al. B-pillar optimization and its effect on side impact safety [J]. Automotive Engineering, 2006, 28(11):972-975.

[2]朱敏, 姬琳, 叶辉. 考虑侧碰的汽车B柱加强板材料性能梯度优化[J]. 吉林大学学报：工学版, 2011, 41(5):1210-1215.

Zhu M, Ji L, Ye H. Optimization of yield stress distribution in B pillar reinforcement panel regarding side crashworthiness [J]. Journal of Jilin University：Eng. and Technol. Ed., 2011, 41(5):1210-1215.

[3]王世魁. 变强度冲压件热成形关键技术研究[D]. 哈尔滨：哈尔滨工业大学, 2014.

Wang S K. Research on the Key Technology of Hot Stamping for Variable Strength Parts[D]. Harbin: Harbin Institute of Technology, 2014.

[4]胡翼, 王超, 徐峰祥, 等. 硼钢板热冲压成形过程接触热阻研究[J].锻压技术,2018,43(7):147-152.

Hu Y, Wang C, Xu F X, et al. Research on thermal contact resistance for boron steel sheet in hot stamping process [J]. Forging & Stamping Technology, 2018, 43(7):147-152.

[5]刘迪辉, 万雨娴, 张文甲. 热冲压模具冷却系统流速均匀优化研究[J]. 锻压技术, 2017, 42(12):104-108.

Liu D H, Wan Y X, Zhang W J. Research on flow rate uniform optimization of hot stamping die cooling system [J]. Forging & Stamping Technology, 2017, 42(12):104-108.

[6]谭海林, 张宜生, 桂中祥, 等. 奥迪B柱热冲压成形热-力-相变耦合仿真分析[J]. 热加工工艺, 2013, 42(1):67-69.

Tan H L, Zhang Y S, Gui Z X, et al. Simulation analysis on thermo-mechanical metallurgical coupling of hot stamping audi B-pillar punching forming [J]. Hot Working Technology, 2013, 42(1):67-69.

[7]Bardelcik A, Worswick M J, Winkler S, et al. A strain rate sensitive constitutive model for quenched boron steel with tailored properties [J]. International Journal of Impact Engineering, 2012, 50:49-62.

[8]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.

[9]邓偲瀛. 模具分区冷却因素对热成形硼钢性能的影响[D]. 大连：大连理工大学, 2013.

Deng S Y. Influence of Tailored Tempering Factors on the Mechanical Properties of Boron Steels within Hot Stamping [D]. Dalian: Dalian University of Technology, 2013.

[10]赵运运, 李亨, 李明, 等. 汽车B柱高强度钢热冲压工艺[J]. 锻压技术, 2017,42(2):66-71.

Zhao Y Y, Li H, Li M, et al. Hot stamping process of high-strength-steel for automotive B-pillar [J]. Forging & Stamping Technology, 2017, 42(2):66-71.

[11]Johnson W A, Mehl R F. Reaction kinetics in processes of nucleation and growth [J]. Trans. AIME, 1939, 135(8):396-415.

[12]Avrami M. Kinetics of phase change I-General theory [J]. Journal of Chemical Physics, 1939, 7(12):1103-1112.

[13]Avrami M. Granulation, phase change, and microstructure-kinetics of phase change III [J]. Journal of Chemical Physics, 1941, 9(2):177-184.

[14]Koistinen D P, Marburger R E. A general equation prescribing the extent of the austenite-martensite transformation in pure iron-carbon alloys and plain carbon steels [J]. Acta Metallurgica, 1959, 7(1):59-60.

[15]Mcmurtrie D G, Magee C L. Average volume of martensite plates during transformation [J]. Metallurgical Transactions, 1970, 1(11):3185-3191.

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