锻压技术

某曲轴热模锻成形工艺设计及优化

英文标题：Design and optimization on hot die forging process for a crankshaft

作者：刘绍波李晓峰

分类号：TG316；TG146.4

出版年,卷(期):页码：2023,48(8):57-65

摘要：

为控制某曲轴的模锻成形质量、避免锻造缺陷的产生。首先，通过热压缩实验获取了40Cr钢在不同温度和应变速率下的流变数据，并用Hansel-Spittel方程进行了拟合，获得了40Cr钢的本构关系，为模锻成形工艺仿真提供了精确的材料数据。等温压缩实验表明：应变速率和温度对40Cr钢的应力水平有显著性影响；当应变速率和应变相同时，应力随着温度的增加而降低；当温度和应变相同时，应力随着应变速率的增加而增加。在低应变速率、高温条件下，材料具有显著的应力峰值；这是由于温度越高、应变速率越低，材料在变形过程中具有足够的能量和时间进行动态再结晶软化。随后，基于金属稳定热加工理论建立了40Cr钢的热加工图，并对压缩试样进行微观组织分析，验证了热加工图的合理性。基于热加工图得到了某曲轴的成形温度推荐范围为900~1000 ℃、应变速率为0.01~0.1 s-1。最后，为了解决某曲轴平衡块填充不满的问题，提出了基于拉丁超立方抽样、数值仿真获取样本、克里金模型构建响应面、遗传算法优化的策略，数值仿真和生产试制结果验证了该策略能够得到充填完整、无锻造缺陷的曲轴锻件，可提升成形质量、减少试错成本。此外，实验试制也验证了选取的成形温度和应变速率能够得到组织细小且均匀的锻件。

To control the die forging quality of a crankshaft and avoid forging defects, the rheological data of 40Cr steel at different temperatures and strain rates were obtained by hot compression experiments, and the constitutive relationship of 40Cr steel was obtained by fitting with Hansel-Spittel equation to provide accurate material data for die forging process simulation. Isothermal compression experiment shows that the strain rate and temperature have significant effects on the stress level of 40Cr steel. When the strain rate and strain are the same, the stress decreases with the increasing of temperature, and when the temperature and strain are the same, the stress increases with the increasing of strain rate. Under the condition of low strain rate and high temperature, the material has a significant stress peak. This is because that the higher the temperature is, the lower the strain rate is, the material has enough energy and time for dynamic recrystallization softening during the deformation. Subsequently, the hot processing map of 40Cr steel was established based on the metal stable hot processing theory, and the rationality of the hot processing map was verified by microstructure analysis of compressed samples. Based on the hot processing map, the recommended forming temperature range of a certain crankshaft is 900-1000 ℃, and the strain rate is 0.01-0.1 s-1. Finally, in order to solve the problem of insufficient filling for a certain crankshaft balance block, a strategy based on Latin hypercube sampling, numerical simulation for sample obtainment, Kriging model for response surface construction and genetic algorithm optimization was proposed. The results of numerical simulation and production trial production verify that the strategy can obtain crankshaft forgings with complete filling and no forging defects, improve the forming quality, and reduce the cost of trial and error. In addition, the trial production also verifies that the selected forming temperature and strain rate can obtain the forgings with fine and uniform structure.

基金项目：

重庆市教委科研项目（KJQN201904001）

作者简介：刘绍波（1986-），男，学士，实验师,E-mail：LSB3119@163.com

参考文献：

[1]朱若岭, 李静, 程秋云. 内燃机用曲轴成形工艺分析及组织模拟研究[J]. 时代汽车, 2022，(7):151-152.

Zhu R L, Li J, Cheng Q Y. Forming process analysis and microstructure simulation of crankshaft for internal combustion engine[J]. Auto Time, 2022，(7):151-152.

[2]Jiao A Y, Chen F L, Liu B H, et al. Failure analysis of a diesel engine crankshaft[J]. Metalurgija, 2020, 59(1): 113-116.

[3]卢占盈, 王华辉, 李佩琪, 等. 曲轴制造工艺研究进展[J]. 汽车零部件, 2019，(2):74-77.

Lu Z Y, Wang H H, Li P Q, et al. Progress in crankshaft manufacturing process[J]. Automobile Parts, 2019，(2):74-77.

[4]袁磊, 冉均均. 34CrNiMo6钢三拐曲轴热模锻成形工艺方案设计及数值模拟分析[J]. 锻压技术, 2022, 47(8):7-14.

Yuan L, Ran J J. Process scheme design and numerical simulation analysis on hot die forge for 34CrNiMo6 steel three-turn crankshaft[J]. Forging & Stamping Technology, 2022, 47(8):7-14.

[5]郑赣. 发动机曲轴热锻数值模拟及工艺优化[D]. 上海：上海工程技术大学, 2020.

Zheng G. The Numerical Simulation and Process Optimization of Engine Crankshaft Hot Forging[D]. Shanghai:Shanghai University of Engineering Science, 2020.

[6]刘竞成. 曲轴锻造成形工艺模拟及模具设计研究[J]. 黑龙江科学, 2019, 10(20):23-24，27.

Liu J C. Research on simulation and die design of crankshaft forging process[J]. Heilongjiang Science, 2019, 10(20):23-24，27.

[7]唐艳, 杜绍贵, 何正海. 某新型内燃机车曲轴镦锻成形工艺研究[J]. 大型铸锻件, 2020，(6):13-16，20.

Tang Y, Du S G, He Z H. Research on the upsetting forming process of a new diesel locomotive crankshaft[J]. Heavy Castings and Forgings, 2020，(6):13-16，20.

[8]肖展开, 梅益, 罗宁康, 等. 基于神经网络航空发动机曲轴加工工艺设计优化[J]. 锻压技术, 2022, 47(6):35-46，86.

Xiao Z K, Mei Y, Luo N K, et al. Design and optimization on machining process for aircraft engine crankshaft based on neural network[J]. Forging & Stamping Technology, 2022, 47(6):35-46，86.

[9]贾俊林, 蒋伟斌, 赵艳荣, 等. 一种三拐曲轴整体锻造方法[J]. 特钢技术, 2020, 26(4):38-39.

Jia J L, Jiang W B, Zhao Y R, et al. An integral forging method for three crank shafts[J]. Special Steel Technology, 2020, 26(4):38-39.

[10]Chen L, Sun W Y, Lin J, et al. Modelling of constitutive relationship, dynamic recrystallization and grain size of 40Cr steel during hot deformation process[J]. Results in Physics, 2019, 12(1): 784-792.

[11]杨怡思, 陈学文, 张博, 等. 基于粒子群算法的GCr15钢温热成形Hansel-Spittel本构模型参数反求优化方法[J]. 材料热处理学报, 2022, 43(7):147-156.

Yang Y S, Chen X W, Zhang B, et al. Reverse optimization method of Hansel-Spittel constitutive model parameters for warm forming of GCr15 steel based on particle swarm optimization[J]. Transactions of Materials and Heat Treatment, 2022, 43(7):147-156.

[12]Narayana Murty S V S, Nageswara Rao B, Kashyap B P. Identification of flow instabilities in the processing maps of AISI 304 stainless steel[J]. Journal of Materials Processing Technology, 2005, 166(2): 268-278.

[13]罗应娜.34CrNiMo6曲轴热成形工艺研究及优化[J].塑性工程学报,2023,30(2):70-78.

Luo Y N. Research and optimization of hot forming process of 34CrNiMo6 crankshaft[J]. Journal of Plasticity Engineering,2023,30(2):70-78.

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