成形力的求解及其在模具结构优化中的应用
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摘要
面对汽车冲压模具竞争激烈的现状,缩短产品的设计周期,提升设计质量,降低模具成本具有非常重要的意义,然而随着模具结构越来越复杂,结构参数不断增多,求解规模不断扩大,传统方法已不能满足产品设计的效率及精度要求。因此,在汽车冲压模具结构设计过程中迫切需要引入实时计算方法,提升复杂结构的分析精度,进而实现结构参数的优化设计。众多学者对实时计算方法进行了研究,寻找计算精度与效率较高的算法,已取得诸多成果,但仍有较多问题值得进一步探索。本文针对金属薄板冲压成形过程中成形力在板料与模具之间传递的关系,提出一种不同网格类型之间的载荷映射计算方法。该方法通过映射单元的精确定位,在板料壳单元与模具实体的单元之间建立了一种对应关系,构建板料单元节点上的成形力与模具网格之间载荷映射的关系模型,从而得到模具表面的精确的载荷分布。将该方法应用于模具结构的优化中,在精确计算模具各部分所受载荷的基础上进行结构优化,得到了满足强度要求的优化结构模型,实现了模具的轻量化。
围绕载荷映射法以及在汽车冲压模具中的应用这一主题,本论文主要开展了以下几方面的研究内容:
(1)对板料成形力精确求解进行研究。在对冲压成形相关理论阐述的基础上,结合工程实例,研究了不同工艺参数及不同单元尺寸对成形力的影响;
(2)基于成形力的求解对模具载荷映射方法进行研究。映射方法研究包括映射方向的选择,节点的精确定位,成形力的插值计算,并对其进行实例分析及其通过实验对比确定方法的正确性。
(3)结合载荷映射及板料成形力的求解对模具结构进行优化分析。利用成形力的精确传递计算方法,得到后续模具结构优化分析的边界条件,对模具进行结构优化设计,从而合理改进模具承载母体结构,使得模具母体达到满足刚强度要求又实现轻量化的目的。
Because of the fiery competition in automobile stamping die industry, it is important to shorten product design cycle, improve quality and reduce the cost. Furthermore, there are many other challenges, such as more complex die structure, increasing structural parameters, and expanding solving scales. Hence, the traditional methods can not keep up with the requirements of design efficiency and accuracy in some extent. Therefore, it is urgent to introduce the real-time calculation methods which can improve the analysis accuracy of complex structure and obtain the optimal parameters of structural design.
With real-time calculation methods, many scholars have developed numerous researches to find high accuracy and efficiency algorithms, but there are still many further explorations. With load mapping method, this paper carries out optimization analysis to die structure. According to the results of optimization analysis, the die structure is improved validly. More details are presented as follows.
1. Precise solution of sheet metal forming force is proposed in this paper. With stamping forming theories and engineering practices, various influence factors of forming force are studied.
2. The load mapping method is investigated based on the solution of forming force. Some key issues is discussed in this method, such as the choice of mapping direction, the accurate position of nodes, the interpolation of forming force. Additionally, some practical cases and experimental verification are presented.
3. The optimization analysis is proposed to die structure based on the load mapping method and solution of sheet metal forming force. The boundary conditions of the die structure optimization analysis can be obtained, through the method of precisely transfer the forming force. Then optimize the design of the die structure to make the die meet the required strength and realize the purpose of lightweight based on the boundary conditions.
围绕载荷映射法以及在汽车冲压模具中的应用这一主题,本论文主要开展了以下几方面的研究内容:
(1)对板料成形力精确求解进行研究。在对冲压成形相关理论阐述的基础上,结合工程实例,研究了不同工艺参数及不同单元尺寸对成形力的影响;
(2)基于成形力的求解对模具载荷映射方法进行研究。映射方法研究包括映射方向的选择,节点的精确定位,成形力的插值计算,并对其进行实例分析及其通过实验对比确定方法的正确性。
(3)结合载荷映射及板料成形力的求解对模具结构进行优化分析。利用成形力的精确传递计算方法,得到后续模具结构优化分析的边界条件,对模具进行结构优化设计,从而合理改进模具承载母体结构,使得模具母体达到满足刚强度要求又实现轻量化的目的。
Because of the fiery competition in automobile stamping die industry, it is important to shorten product design cycle, improve quality and reduce the cost. Furthermore, there are many other challenges, such as more complex die structure, increasing structural parameters, and expanding solving scales. Hence, the traditional methods can not keep up with the requirements of design efficiency and accuracy in some extent. Therefore, it is urgent to introduce the real-time calculation methods which can improve the analysis accuracy of complex structure and obtain the optimal parameters of structural design.
With real-time calculation methods, many scholars have developed numerous researches to find high accuracy and efficiency algorithms, but there are still many further explorations. With load mapping method, this paper carries out optimization analysis to die structure. According to the results of optimization analysis, the die structure is improved validly. More details are presented as follows.
1. Precise solution of sheet metal forming force is proposed in this paper. With stamping forming theories and engineering practices, various influence factors of forming force are studied.
2. The load mapping method is investigated based on the solution of forming force. Some key issues is discussed in this method, such as the choice of mapping direction, the accurate position of nodes, the interpolation of forming force. Additionally, some practical cases and experimental verification are presented.
3. The optimization analysis is proposed to die structure based on the load mapping method and solution of sheet metal forming force. The boundary conditions of the die structure optimization analysis can be obtained, through the method of precisely transfer the forming force. Then optimize the design of the die structure to make the die meet the required strength and realize the purpose of lightweight based on the boundary conditions.
引文
[1] Aitharaju V,Liu M,Jennifer D, et al.Integrated Forming Simulations and Die Structural Analysisfor Optimal Die Designs. In: Proceedings of the 6th International Conference and Workshop on Numerical Simulation of 3D Sheet Metal Forming Process, Detroit, USA, 2005, 778(5):96-100
[2]王勖成.有限单元法.第一版.北京:清华大学出版社, 2003
[3]张贵宝.高强度薄板拉深模具结构分析关键技术研究及应用:[上海交通学博士学位论文].上海:上海交通大学, 2008
[4] Welo T, Paulsen F, Brobak T J. The behavior of thin-walled aluminum alloy profiles in rotarydraw bending-a comparison between numerical and experimental results. Journal of Materials Processing Technology. 1994, 45(1-4):173-180
[5]孙继东,林建平,胡巧声,等.金属板料幂指型硬化模型应变强化系数K值研究.塑性工程学报, 2009, 16(1):149-152
[6]黄海锋.基于UG NX平台的汽车覆盖件冲压方向优化.锻压装备与制造技术, 2006, 41(2):61-63
[7]谢晖,杨旭静,成艾国,等.计算机仿真中板料冲压成形压边力的优化.中国机械工程, 2002, 13(22):1910-1914
[8]王国春,成艾国,钟志华.面向设计的车门内板拉延成型分析.机电产品开发与创新, 2006, 19(4):101-104
[9]黄菊花,李慎国,饶进军,等.冲压件成形计算机模拟工艺参数优化方法研究.中国机械工程, 2004,15(7):648-654
[10]宋雪松,蔡中义,李明哲.板材多点成形过程中成形力的数值模拟.吉林大学学报(工学版), 2004, 34(2):226-231
[11]肖海峰,徐艳琴.基于PAM-STAMP 2G的模具结构的优化设计[J].锻压装备与制造技术, 2009, (1):67-68
[12]徐金波,董湘怀.基于有限元分析的汽车覆盖件模具设计及优化[J].锻压技术, 2004,(1):63-67
[13]林新波,李荣先,柳百成,等.利用有限元仿真技术优化模具结构[J].锻压技术, 2005,(2):46-49
[14] Y.Kojima, H.morikawa, T.Misuno. Measurement of pressure distribution in drawing of bars. Journal of Japan Society for Precision Engineering, 1985, 26(295):855-861
[15] S.Matsubara, H.Kudo. Devising and calibration of a simple sensor for determining pressure distribution on tool-workpiece interfaces[J]. Journal of Japan Society for Technology of Plasticity, 1991, 32(364):589-596
[16] S.Matsubara, H.Kudo.Contact pressure characteristics on tool-workpiece interface during plane-strain extrusion of pure aluminium[J]. Journal of Japan Society for Technology of Plasticity, 1991, 32(366):862-867
[17] S.Matsubara, H.Kudo. Distribution of contact pressure on tool-workpiece interface in axisymmetric backward extrusion of aluminium cans[J]. Journal of Japan Society for Technology of Plasticity, 1991, 32(366):868-873
[18] S.Matsubara, H.Kudo. Nonuniform pressure distribution on punch nose surface in axisymmetric cold forging processes. Journal of Japan Society for Technology of Plasticity, 1991, 32(366):874-879
[19] Y.Murata, Y.Yabuki. Measurement of die deformation in forging by capacitive displacement transducer. In: Proceedings of the Fourgh International Conference on Technology of Plasticity, 1993
[20] M.T.Hillery, S.Griffin. An embedded-strain-gauge technique of stress analysis in rod drawing. Journal of Materials Processing Technology, 1994, 47(1-2):1-12
[21] C.MacCormack, J.Monaghan. Failure analysis of cold forging dies using FEA. Journal of Materials Processing Technology, 2001, 117(1-2):209-215
[22] R.Balendra, Y.Qin, X.Lu. Analysis evaluation and compensation of component errors in the net-forming of engineering components. Journal of Materials ProcessingTechnology, 2000, 106(2):204-211
[23] R.Balendra. Nett-shape forming:state-of-the-art. Journal of Materials Processing Technology, 2001, 115(2):172-179
[24] R.Balendra. Overview of"Die-cavity elasticity considerations for net forming (DICAVITY)". Journal of Materials Processing Technology, 2001, 115(2):180-186
[25] R.Balendra, Y.Qin. Research dedicated to the development of advanced metal-forming technologies. Journal of Materials Processing Technology, 2004, 145(2):144-152
[26] X.Lu, R.Balendra. Evaluation of FE models for the calculation of die-cavity compensation. Journal of Materials Processing Technology, 1996, 58(2-3):212-216
[27] X.Lu, R.Balendra. Pressure contours on forming dies:Part II:Finite element simulation. Journal of Materials Processing Technology, 2001, 115(2):220-226
[28] X.Lu, R.Balendra. Finite element simulation for die-cavity compensation[J]. Journal of Materials Processing Technology, 2001, 115(2):227-232
[29] Y.S.Lee, J.H.Lee, T.Ishikawa. Analysis of the elastic characteristics at forging die for the cold forged dimensional accuracy. Journal of Materials Processing Technology, 2002, 130(3):532-539
[30] Y.S.Lee, J.H.Lee, J.U.Choi, et al. Experimental and analytical evaluation for elastic deformation behaviors of cold forging tool. Journal of Materials Processing Technology, 2002, 127(1):73-82
[31] Y.S.Lee, J.H.Lee, Y.N.Kwon, et al. Analysis of the elastic characteristics at die and workpiece to improve the dimensional accuracy for cold forged part. Journal of Materials Processing Technology, 2004, 153(2):1081-1088
[32] Weilong Hu, Amber Wang. Advanced tools and methods to improve durability, stability and tryout robustness of stamping die system,In: Ford technical reports, 2007
[33]陈亮,陈军,张贵宝,等.高强度钢板拉深模具结构有限元分析与试验研究.塑性工程学报, 2008, 15(2):12-45
[34]汤禹成.高强度钢板拉深成形工艺稳健设计及模具结构拓扑优化:[上海交通学博士学位论文].上海:上海交通大学, 2009
[35]张贵宝,陈军,王晓方.基于板料成形数值模拟的冲压模具结构分析方法[J].机械工程学报, 2008, 44(8):174-179
[36] Majumdar A, Bhushan B. Fractal Model of Elastic-plastic Contact between Rough Surfaces.J.Tribol(ASME), 1991, 113(1):1-11
[37]郑林庆.摩擦学原理.北京:高等教育出版社, 1994
[38]贺林,朱均.粗糙表面接触分形模型的提出与发展.摩擦学学报, 1996, 16(4):375-384
[39] Johnson KL.接触力学.徐秉业,罗学富,刘信声,等译.北京:高等教育出版社, 1992
[40] T.BURANATHITI, J.CAO. Benchmark simulation results:automotive underbody crossmember(Benchmark 2), In: Numisheet 2005, 2005, Detroit-USA,
[41]胡平,鲍益东,胡斯博,等.引入工艺因素的汽车车身部件碰撞仿真分析.固体力学学报, 2006, 27(2):148-158
[42]兰箭,张靖暹,张沔利,等.基于弧长法的有限元逆算法在板料成形中的应用.金属铸锻焊技术, 2009, 38(11): 82-85
[43]龙述尧,蒯行成,刘腾喜.计算力学.湖南:湖南大学出版社, 2007
[44] Rozvany G.I.N, Bendsoe M.P, Kirsch U. Layout optimization of structures.Applied Mechanics Reviews, 1996, 48(12):41-118
[45] W.Achtziger , M.P.Bendsoe.Optimal Topology Design of Discrete Structures Resisting Degradation Effects. Structural and Multidisciplinary Optimization, 1999, 17(1),74-78
[2]王勖成.有限单元法.第一版.北京:清华大学出版社, 2003
[3]张贵宝.高强度薄板拉深模具结构分析关键技术研究及应用:[上海交通学博士学位论文].上海:上海交通大学, 2008
[4] Welo T, Paulsen F, Brobak T J. The behavior of thin-walled aluminum alloy profiles in rotarydraw bending-a comparison between numerical and experimental results. Journal of Materials Processing Technology. 1994, 45(1-4):173-180
[5]孙继东,林建平,胡巧声,等.金属板料幂指型硬化模型应变强化系数K值研究.塑性工程学报, 2009, 16(1):149-152
[6]黄海锋.基于UG NX平台的汽车覆盖件冲压方向优化.锻压装备与制造技术, 2006, 41(2):61-63
[7]谢晖,杨旭静,成艾国,等.计算机仿真中板料冲压成形压边力的优化.中国机械工程, 2002, 13(22):1910-1914
[8]王国春,成艾国,钟志华.面向设计的车门内板拉延成型分析.机电产品开发与创新, 2006, 19(4):101-104
[9]黄菊花,李慎国,饶进军,等.冲压件成形计算机模拟工艺参数优化方法研究.中国机械工程, 2004,15(7):648-654
[10]宋雪松,蔡中义,李明哲.板材多点成形过程中成形力的数值模拟.吉林大学学报(工学版), 2004, 34(2):226-231
[11]肖海峰,徐艳琴.基于PAM-STAMP 2G的模具结构的优化设计[J].锻压装备与制造技术, 2009, (1):67-68
[12]徐金波,董湘怀.基于有限元分析的汽车覆盖件模具设计及优化[J].锻压技术, 2004,(1):63-67
[13]林新波,李荣先,柳百成,等.利用有限元仿真技术优化模具结构[J].锻压技术, 2005,(2):46-49
[14] Y.Kojima, H.morikawa, T.Misuno. Measurement of pressure distribution in drawing of bars. Journal of Japan Society for Precision Engineering, 1985, 26(295):855-861
[15] S.Matsubara, H.Kudo. Devising and calibration of a simple sensor for determining pressure distribution on tool-workpiece interfaces[J]. Journal of Japan Society for Technology of Plasticity, 1991, 32(364):589-596
[16] S.Matsubara, H.Kudo.Contact pressure characteristics on tool-workpiece interface during plane-strain extrusion of pure aluminium[J]. Journal of Japan Society for Technology of Plasticity, 1991, 32(366):862-867
[17] S.Matsubara, H.Kudo. Distribution of contact pressure on tool-workpiece interface in axisymmetric backward extrusion of aluminium cans[J]. Journal of Japan Society for Technology of Plasticity, 1991, 32(366):868-873
[18] S.Matsubara, H.Kudo. Nonuniform pressure distribution on punch nose surface in axisymmetric cold forging processes. Journal of Japan Society for Technology of Plasticity, 1991, 32(366):874-879
[19] Y.Murata, Y.Yabuki. Measurement of die deformation in forging by capacitive displacement transducer. In: Proceedings of the Fourgh International Conference on Technology of Plasticity, 1993
[20] M.T.Hillery, S.Griffin. An embedded-strain-gauge technique of stress analysis in rod drawing. Journal of Materials Processing Technology, 1994, 47(1-2):1-12
[21] C.MacCormack, J.Monaghan. Failure analysis of cold forging dies using FEA. Journal of Materials Processing Technology, 2001, 117(1-2):209-215
[22] R.Balendra, Y.Qin, X.Lu. Analysis evaluation and compensation of component errors in the net-forming of engineering components. Journal of Materials ProcessingTechnology, 2000, 106(2):204-211
[23] R.Balendra. Nett-shape forming:state-of-the-art. Journal of Materials Processing Technology, 2001, 115(2):172-179
[24] R.Balendra. Overview of"Die-cavity elasticity considerations for net forming (DICAVITY)". Journal of Materials Processing Technology, 2001, 115(2):180-186
[25] R.Balendra, Y.Qin. Research dedicated to the development of advanced metal-forming technologies. Journal of Materials Processing Technology, 2004, 145(2):144-152
[26] X.Lu, R.Balendra. Evaluation of FE models for the calculation of die-cavity compensation. Journal of Materials Processing Technology, 1996, 58(2-3):212-216
[27] X.Lu, R.Balendra. Pressure contours on forming dies:Part II:Finite element simulation. Journal of Materials Processing Technology, 2001, 115(2):220-226
[28] X.Lu, R.Balendra. Finite element simulation for die-cavity compensation[J]. Journal of Materials Processing Technology, 2001, 115(2):227-232
[29] Y.S.Lee, J.H.Lee, T.Ishikawa. Analysis of the elastic characteristics at forging die for the cold forged dimensional accuracy. Journal of Materials Processing Technology, 2002, 130(3):532-539
[30] Y.S.Lee, J.H.Lee, J.U.Choi, et al. Experimental and analytical evaluation for elastic deformation behaviors of cold forging tool. Journal of Materials Processing Technology, 2002, 127(1):73-82
[31] Y.S.Lee, J.H.Lee, Y.N.Kwon, et al. Analysis of the elastic characteristics at die and workpiece to improve the dimensional accuracy for cold forged part. Journal of Materials Processing Technology, 2004, 153(2):1081-1088
[32] Weilong Hu, Amber Wang. Advanced tools and methods to improve durability, stability and tryout robustness of stamping die system,In: Ford technical reports, 2007
[33]陈亮,陈军,张贵宝,等.高强度钢板拉深模具结构有限元分析与试验研究.塑性工程学报, 2008, 15(2):12-45
[34]汤禹成.高强度钢板拉深成形工艺稳健设计及模具结构拓扑优化:[上海交通学博士学位论文].上海:上海交通大学, 2009
[35]张贵宝,陈军,王晓方.基于板料成形数值模拟的冲压模具结构分析方法[J].机械工程学报, 2008, 44(8):174-179
[36] Majumdar A, Bhushan B. Fractal Model of Elastic-plastic Contact between Rough Surfaces.J.Tribol(ASME), 1991, 113(1):1-11
[37]郑林庆.摩擦学原理.北京:高等教育出版社, 1994
[38]贺林,朱均.粗糙表面接触分形模型的提出与发展.摩擦学学报, 1996, 16(4):375-384
[39] Johnson KL.接触力学.徐秉业,罗学富,刘信声,等译.北京:高等教育出版社, 1992
[40] T.BURANATHITI, J.CAO. Benchmark simulation results:automotive underbody crossmember(Benchmark 2), In: Numisheet 2005, 2005, Detroit-USA,
[41]胡平,鲍益东,胡斯博,等.引入工艺因素的汽车车身部件碰撞仿真分析.固体力学学报, 2006, 27(2):148-158
[42]兰箭,张靖暹,张沔利,等.基于弧长法的有限元逆算法在板料成形中的应用.金属铸锻焊技术, 2009, 38(11): 82-85
[43]龙述尧,蒯行成,刘腾喜.计算力学.湖南:湖南大学出版社, 2007
[44] Rozvany G.I.N, Bendsoe M.P, Kirsch U. Layout optimization of structures.Applied Mechanics Reviews, 1996, 48(12):41-118
[45] W.Achtziger , M.P.Bendsoe.Optimal Topology Design of Discrete Structures Resisting Degradation Effects. Structural and Multidisciplinary Optimization, 1999, 17(1),74-78