高强度钢板扭曲回弹特性及控制方法研究
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摘要
扭曲回弹是冲压成形过程中常出现的一种回弹形式,随着汽车用钢强度的提高,扭曲回弹更加明显。汽车零件产生的扭曲回弹非常难以控制,往往涉及到对零件型面的调整,风险较大且工程繁琐,使得工程师对于采用高强度钢板的零件比较慎重,然而基于汽车轻量化和安全性的考虑,高强度钢板在汽车车身上的应用越来越普及。扭曲回弹控制不了,会严重影响整车的装配精度和增加焊装的难度,因此,扭曲回弹问题一直是汽车工业界和学术界关注的热点。
     本研究基于工程实际应用,首先从实际生产中出现的各种扭曲回弹形式进行归类和总结,分析了产生扭曲回弹零件的基本特征,并对产生扭曲回弹的基本原因和影响因素进行了探讨研究。本文提出了高强钢零件冲压后扭曲回弹问题的分析方法、评价方法和控制方法。
     本研究的主要工作包括以下几个方面:
     1.在广泛调查扭曲回弹现象的基础上,对容易产生扭曲回弹的汽车车身零件进行了分类,研究整理出高强钢零件冲压后产生扭曲回弹的主要基本特征。通过实际零件如A柱铰链加强板、门槛件等零件的扭曲回弹现象分析,提出零件的“抗扭刚度”和“残余扭矩”是导致扭曲回弹的主要原因,并提出了常用的减小扭曲回弹的方法和工艺。
     2.提出一种考虑特征截面卷曲回弹的解析法用于预测特征截面的回弹量,并将卷曲效应叠加到回弹角的计算结果中,使得预测方法更加准确,通过U型冲压实例对该方法进行了验证,结果表明该解析算法具有较高的计算精度。提出基于该解析法预测零件整体扭曲回弹趋势的方法,将扭曲回弹定义为“初始回弹”和“相互影响”两个过程,通过解析法分析截面的初始回弹,结合零件的形状特点分析不同截面之间的相互影响作用,从而实现对零件扭曲回弹趋势的预测,并对具有拐角特征、变截面特征等的典型零件的扭曲回弹趋势进行了实例分析。
     3.分析了汽车冲压件产生扭曲回弹的基本特征,即不平衡拉深特征、变截面特征和拐角特征,以实验为基础,采用科学实验设计方法结合仿真分析手段分析了这些特征产生扭曲回弹的基本原因,并以这些基本特征为基础,研究了汽车零件的基本特征尺寸、冲压材料、成形工艺等因素对扭曲回弹的影响规律。
     4.提出可用于预测实际零件扭曲回弹趋势和规律的截面运动法,该方法采用回弹前后典型截面的运动参数作为零件扭曲回弹的评价指标,对零件的扭曲回弹进行了量化,通过特征截面和扭曲回弹参数描述零件的扭曲回弹。应用实例表明,该方法能够较准确地计算复杂零件的扭曲回弹量,对指导汽车零件扭曲回弹的控制具有较强的实用性。
     5.提出了一种基于截面运动规律的扭曲回弹控制方法,该方法应用截面运动法获取典型截面扭曲回弹参数,采用反向补偿因子计算扭曲回弹截面控制线,利用该截面控制线生成扭曲回弹补偿型面。应用实例表明,利用基于截面运动规律的扭曲回弹控制方法可对模具型面进行快速调整,节省了高强钢车身零件的制造时间,并可提高零件的尺寸精度。
Usually there is a problem that the torsion springback of panel is difficult to be controlled in the stamping process, especially using HSS (High Strength Steel). Based on the consideration of lightweight and safety, the application of HSS in automotive panel is more and more popular. It will make a bad accuracy in the car assembly if the springback can’t be controlled well. Torsion springback of automobile part is one of the main forms of springback, which is complex and hard to control and brings difficulties of manufacture precision. So, torsion springback problem is always a hotspot in automotive industry group and academia.
     The research was based on practical application of engineering, Firstly, various forms of torsion springback were classified and summarized. Secondly, basic features of torsion springback were analyzed. Finally, basic reasons and effect factors of torsion springback were studied. Based on the engineering practice, this paper contains torsion springback analysis, evaluation methods and control methods. Main works of this paper are presented as follows:
     1.According to the widespread investigation on torsion springback, the auto parts which were more likely to bring torsion springback were classified, summaries of main basic characteristic of torsion springback were obtained. The general forms of torsion springback of the HSS by actual parts were explained, such as A pillar reinforcement, door threshold etc. A method named“torsion stiffness”was proposed to analysis the reasons for torsion springback and influencing factors, commonly used methods and techniques of production were proposed to reduce torsion springback by the aspects including remaining torque and the torsion stiffness.
     2.An analytical method to calculate the springback of characteristics section was suggested, sidewall curl was also considered and taken account into springback computation, this strategy improves the accuracy of the proposed method. The method was validated by the U stamping, and it indicated that the method has a higher accuracy. Furthermore, a method to predict tendency of torsion springback was proposed, the process of torsion springback can be divided into "primitive springback" and "mutual influence". Firstly, the primitive springback of section was calculated by analytical method, and then, shape features were taken into account to analysis mutual influence of different sections. Meanwhile, by this method, we could analysis the causes of torsion springback. Cases study for basic feature with turning shapes and various section shapes were carried out. The torsion springback of the given parts were analyzed by finite element method, and then some measures to promote accuracy and predict tendency of torsion springback were put forward.
     3.Some basic features such as parts with turning shapes, parts with various section shapes, non-uniform material flow in stamping process were proposed. Based on experiments and simulation of FEM, cases to the effect of torsion springback were studied, such as the basic feature size, properties of stamping materials, stamping techniques etc.
     4.A novel method to evaluate parts' torsion springback by springback movement of characteristic cross-section method was proposed. This method could obtain the parameters of springback movement in the characteristic cross-sections, this paper attempts to represent parts' torsion springback by parameters. A program was developed to determine the deformation of characteristic section, the deformable movement included displacement and rotation, and this program divided characteristic sections with several areas by convergence estimation. The paper studied on a part’s springback with arched surface by experiment and simulation analysis, the result verified validity of this model.
     5.A system which can control springback is presented based on the springback movement of characteristic cross-section method. Firstly, the result of springback could be calculated by FE system or obtained by scan way. Secondly, the parameters of springback movement in the characteristic cross-sections could be analyzed by springback movement of characteristic cross-section method (SMCS). Thirdly, springback control section could be obtained based on the parameters of springback movement by compensation factor method. Finally, based on the origin CAD surface and the control section of springback, the mould was compensated for springback by application of shape global deformation method. The practice engineering cases proved that the system can save more time to deal with springback of parts with arched surface, the result of springback compensation is right and applied and the method is worth to spread.
引文
[1] Gan W, Wagoner R H. Die design method for sheet springback. International Journal of Mechanical Sciences, 2004, 46 (7): 1097-1113
    [2]宋黎,杨坚,黄天泽.板料弯曲成形的回弹分析与工程控制综述.锻压技术, 1996, (1): 18-22
    [3] Willie Bernert, Michael Bzdok, John Davis et al. Advanced High-Strength Steel Product and Process Applications Guidelines. Auto/Steel Partnership, 2008
    [4]邓泽英.车身轻量化材料的应用.重型汽车, 2000, (4): 16-18
    [5]陆匠心,王利.高强度汽车钢板的生产与使用.汽车工艺与材料, 2004, (2): 1-6
    [6] Burchitz I. Springback improvement of its predictability Literature study report. Netherlands Institute for Metals Research, 2005
    [7] Takehide Senuma. Physical Metallurgy of Modern High Strength Steel Sheets. ISIJ International, 2001, 41(6): 520-532.
    [8]李玉璇.基于耐撞性数值仿真的汽车车身轻量化研究: [上海交通大学博士学位论文].上海:上海交通大学, 2003, 60-67
    [9]蒋浩民,苏海波,陈新平等.一种多弯曲变截面轿车副车架液压成形研究.第十一届全国塑性工程学术年会, 2009, 153-157
    [10]冯美斌.汽车轻量化技术中新材料的发展及应.汽车工程, 2006, 28(3): 26-30
    [11]陈小视,匡永祥.铝及铝合金在交通运输业中的应用.铝加工, 1993, 12(2): 12-14
    [12]康永林.国内外汽车板的现状需求和发展趋势.中国冶金, 2003, 6
    [13] Guofei CHEN, Xiaoming CHEN, Ming F SHI. Material and Processing Modeling of Dual Phase Steel Front Rails for Crash. AHSSS PROCEEDINGS, 1998, 161-170
    [14] ADVANCED HIGH STRENGTH STEEL (AHSS) APPLICATION GUIDELINES. AS/P, 2006
    [15] Takita M, Ohashi H. Application of high strength steel sheets for automobiles in Japan. La Revue De metallurgies- CIT, Japan, 2001, 899-909
    [16]徐祖耀,马氏体相变与马氏体.第二版.科学出版社, 1999, 690-691
    [17]王利,陆匠心.中国汽车工业的发展与钢厂的技术应对. 2007年中国汽车工程学会年会, 2007, 211-217
    [18] Kwang Kyun Park, Seung Taik Oh, Suk Min Baeck. In-situ Deformation Behavior of Retained Austenite on TRIP Steel. Material Science Forum, 2002, 408-412
    [19]付泽民,莫健华,王永骥,等.金属板材折弯成形回弹预测及凸模几何参数反求.华中科技大学学报:自然科学版, 2009, 37(11): 86-89.
    [20]钟志华,李光耀.薄板冲压成型过程的计算机仿真与应用.北京:北京理工大学出版社, 1998, 27-32
    [21] Marquette P, Chambard A, Ling D, et al. Best practice methodology for springback prediction. compensation and assembly. IDDRG 2008 International Conference, 2008, 346-351
    [22] Cedric Xia Z, Craig E Miller, Maurice Lou. A Benchmark Test for Springback: Experimental Procedures and Results of a Slit-Ring Test. SAE Technical Paper Series, 2005, 211-218
    [23] Han S S, Park K C. An investigation of the factors influencing springback by emprical a simulative techniques, Numisheet’99, France, 13-17
    [24] Gau J T, Kinzel G L. An experimental inverstigations of the influence of the Bauschinger effect on springback predictions. Journal of Materials Processing Technology, 2001, 108: 369-375
    [25] Thomson P F, Kim J K. Springback and side-wall curl of Galvanized and Galvalume steel sheet. Journal of Mechanical Working Technology, 1989, 19: 233-238
    [26] Livatyali H, Wu H C, Altan T. Prediction and elimination of springback in straight flanging using computer-aided design methods: Part 2: FEM predictions and tool design. Journal of Materials Processing Technology, 2002, 120(1-3): 348-354
    [27] Inamdar M V, Date P P, Sabnis S V. On the effects of geometric parameters on springback in sheets of five materials subjected to air vee bending. Journal of Materials Processing Technology, 2002, 123(10): 459-463
    [28] Tan Z, Pesson B, Magnusson. An empiric model for controlling springback in V-die bending of sheet metals. Journal of Materials Processing Technology, 1992, 34: 449-455
    [29]刘克进.薄板冲压回弹试验研究及数值模拟对比分析: [湖南大学硕士学位论文],长沙:湖南大学, 2004
    [30] Burchitz I. Springback improvement of its predictability Literature study report. Netherlands Institute for Metals Research, 2005
    [31] Makinouchi A E, Nakamachi E, Onate, Wagoner R H, editors. NUMISHEET’93. The Institute of Physical and Chemical Research, 1993
    [32] Ayres RA. SHAPESET: a process to reduce sidewall curl springback in high strength steel rails. Journal of Applied Metal working, 1984, 3(2): 127-134
    [33] Arden W D, Geng L M, Matlock D K, et al. Measurement of springback. International Journal of Mechanical Sciences, 2002, 44(17): 79-101
    [34] Hill R. The Mathematical Theory of Plasticity. London: Oxford University Press, 1950
    [35]余同希,张亮炽.塑形弯曲理论及其应用.北京:科学出版社, 1992, 45-86
    [36] ALY EL-DOMIATY, SHABAIK A H. Bending of work-hardening metals under the influence of axial load. Journal of mechanical working technology, 1984, 10: 57-66
    [37] Zhang Z T, Hu S J. Stress and residual stress distributions in plane strain bending. International Journal of Mechanical Sciences, 1998, 40(6): 533-543
    [38] Zhang Z T, Lee D. Development of a new model for plane strain bending and springback analysis. Journal of materials engineering and performance, 1995, 4: 291-299
    [39] Luc Papeleux, Jean-Philippe Ponthot. Finite element simulation of springback in sheet metal forming. Journal of Materials Processing Technology, 2002, 126: 785-791
    [40] Pourboghrat F, Chung K, Richmond O. Hybrid Membrane/Shell Method for Rapid Estimation of Springback in An Isotropic Sheet MetaIs. Journal of Applied Mechanics, 1998, 65(3): 671-684
    [41] Meindersa T, Burchitz I A, Bontea M H A, et al. Numerical product design: Springback prediction, compensation and optimization. International Journal of Machine Tools & Manufacture, 2008, 48: 499-514
    [42] Peng Chen, Muammer Koc. Simulation of springback variation in forming of advanced high strength steels. Journal of Materials Processing Technology, 2007, 190: 189-198
    [43] Naceur H, et al. Response surface methodology for the rapid design of aluminum sheet metal forming parameters. Materials and Design, 2008, 29: 781-790
    [44] Meinders T, et al. Numerical product design: Springback prediction,compensation and optimization. International Journal of Machine Tools & Manufacture, 2008, 48: 499-514
    [45] Papatriantafillou I, Agoras M, Aravas N, et al. Constitutive modeling and finite element methods for TRIP steels. Computer methods in applied mechanics and engineering, 2006, 195: 5094-5114
    [46] Firat M. Computer aided analysis and design of sheet metal forming processes. Materials & Design, 2006, 23(3): 1-11.
    [47] Ogawa H, Makinouchi A. Development of an elasto-plastic FE code for accurate prediction of springback in sheet bending processes and It’s validation by experiments. Progress in Computational Analysis of Inelastic Strutures, International centre for theoretical physics, 1993, 1641-1646
    [48] Brunet M. A finite analysis of springback in plan folding with binders of high strength steel sheets, Computational Methods for Predicting Material Processing Defects, 1987,11: 47-56
    [49] Finn MJ, Gallbraith PC. Use of coupled explicit-implicit solver for calculating springback in automotive body panels. Journal of Metal Processing Tech, 1995, 50(1-4): 395-409
    [50] Kawka M, Makinouchi A. Analysis of Multi-Operation Automotive Sheet Metal Forming Processes, Advanced Technology of Plasticity 1993- Proceeding of the Fourth International Conference on Technology of Plasticity, 1993, 1811-1816
    [51]汪晨.板料成形回弹的数值模拟及考虑回弹补偿的模具设计方法研究: [上海交通大学博士学位论文].上海:上海交通大学, 1998
    [52]王金彦.板料成形数值模拟的新型有限元理论模型研究: [上海交通大学博士学位论文].上海:上海交通大学, 2006
    [53]张东娟.板料冲压成形回弹理论及有限元数值模拟研究: [上海交通大学博士学位论文].上海:上海交通大学, 2006
    [54]江莅煌.板料冲压成形及回弹有限元数值模拟分析研究: [南京理工大学硕士学位论文].南京:南京理工大学, 2007
    [55] Mullan H B. Improved prediction of springback on final formed components. Journal of Materials Processing Technology, 2004, 464- 471
    [56] Ninshu Ma, Yasuyoshi Umezu, Yuko Watanabe et al. Springback prediction by yoshida-uemori model and compensation of tool surface using JSTAMP. Proc. of NUMISHEET2008, Part-A, 2008, 473-478
    [57]龚志辉,李光耀,钟志华等.基于仿真误差补偿模型的回弹补偿新方法.中国机械工程, 2008, 19(11): 1358-1362
    [58] Rolfe B F, Cardew-Hall M J, Abdallah S M. A Shape Error Metric for Sheet Metal Forming and Its Application to Springback. Journal of Manufacturing Science and Engineering, 2003, 125: 468-475
    [59] Naceur H, Guo Y Q, Ben2Elechi S. Response surface methodology for design of sheet forming parameters to control springback effects. Computers & Structures, 2006, 6: 1-13
    [60] Ghouati O, Joannic D, Gelin J C. Optimization of process parameters for the control of springback in deep drawing. NUMIFORM’98, 1998, 819-824
    [61] Shawn Cheng H, Cao J, Xia Z C. An accelerated springback compensation method. International Journal of Mechanical Sciences, 2007, 49 (3): 267-279
    [62] Lan F, Chen J, Lin J. A method of constructing smooth tool surfaces for FE prediction of springback in sheet metal forming. Journal of Materials Processing Technology, 2006, 177: 382-385
    [63] Gan W, Wagoner R H. Die design method for sheet springbaek. International Journal of Mechanical Sciences, 2004, 46: 1097-1113
    [64] Lingbeek R, Huetink J, Ohnimus S, et a1. The development of a finite elements based springback cornpensation tool for sheet metal metal products. Journal of Materials Proceeding Technology, 2005, 169(1): 115-125
    [65] Karafillis A P, Boyce M C. Tooling design in sheet metal forming using springback calculations, Int. J. Mech. Sci, 1992, 34(2): 113-131
    [66] Karafillis A P, Boyce M C. Tooling and binder design for sheet metal forming processes compensating springback error, Int. J. Mech. Tools Manufact., 1996, 36 (4): 503-526
    [67] Cheng H S, Cao J, Xia z C. An accelerated springback compensation method. International Journal of M echanical Sciences, 2007, 49(3): 267-279
    [68] Webb R D. Hardt D E. A transfer function description of sheet metal forming for process control. Transaction of the ASME, Journal of Engineering for Industry, 1991, 113: 44-52
    [69] Wu L W, Du C Q, etc. Iterative FEM die surface design to compensate for springback in sheet metal stampings, NUMISHEET’95, 1995, 637-641
    [70] Oral S, Darendeliler H. The optimum die profile for the cylindrical bending of plates, J. Mats. Processing Technology, 1997, 70: 151-155
    [71]邵鹏飞,王秀喜,车玫.板料成形中的回弹计算和模具修正.机械强度, 2001, 23(2): 187-189
    [72] Du C, Chen X M, et al. Correlation of FEA Prediction And Experiments On Dual-Phase Steel Automotive Rails, Materials Processing and Design: Modeling, Simulation and Applications, 2007, 2(908): 943-948
    [73] Shu J S, Hung C H. Finite element analysis and optimization of springback reduction: The“Double-bend”technique, Int. J. Mach. Tools anufact., 1996, 136(4): 423-434
    [74] Umehara Y. Technologies for the more precise press forming of automobile parts, J. Mats. Processing Technology, 1990,1 (22): 239-256
    [75]韩俊,林刚,詹捷等.高强度钢板汽车A柱回弹控制与工艺优化.模具工业, 2010, 1: 35-38
    [76] Banu M, Takamura M, Hama T, et al. Simulation of springback and wrinkling in stamping of a dual phase steel rail-shaped part. Journal of Materials Processing Technology, 2006, 10 (4): 178-184
    [77] Chen X M, Drouiru J J. Stamping and Crush Performance of Dual Phase Steel. SAE, 2001-01-3074, 1-8
    [78]单体坤,张卫刚. TRIP钢薄板冲压的回弹研究.塑性工程学报, 2008, 15(4): 19-23
    [79]罗云华,王磊.高强钢板冲压回弹影响因素研究.锻压技术, 2009, 34(1): 23-26
    [80]蒋浩民,陈新平,石磊等.先进高强度钢板的冲压成形特性及其应用.塑性工程学报, 2009, 16(4): 183-186
    [81]王利,杨雄飞,陆匠心.汽车轻量化用高强度钢板的发展,钢铁, 2006, 41(9): 1-8
    [82] Bahloul R, Ben-Elechi S B, Potiron A. Optimisation of springback predicted by experimental and numerical approach by using response surface methodology. Journal of Materials Processing Technology, 2006, 173: 101-110
    [83]朱东波,马雷,李涤尘等.复杂形状板料冲压件回弹评价指标研究.机械科学与技术, 2000, 19(6): 953-955
    [84]龚志辉,钟志华,杨旭静.汽车外覆盖件回弹评价方法及应用.汽车工程, 2007, 4(29): 351-354
    [85] Wu Longwu. Generate Tooling Mesh by FEM Virtual Forming Model for Springback Compensation in Die Surface Design of Sheet Metal Stamping. SAE transactions, 1996, 105(55): 643-649
    [86] Karafillis A P, Boyce M C. Tooling and Binder Design for Sheet Metal Forming Processes Compensating Springback Error. International Journal ofMachine Tools Manufacture, 1996, 36(4): 503-526
    [87]吴磊,李光耀,曹昭展.高强钢材料性能对汽车零件扭曲回弹的影响.塑性工程学报, 2009, 16(3): 13-17
    [88] Xu Y G, Liu G R, Wu Z P. A Novel Hybrid Genetic Algorithm Using Local Optimizer Based on Heuristic Pattern Move. Appl., Artif. Intelligence, 2001, 15(7): 601-631
    [89]龚志辉.基于逆向工程技术的汽车覆盖件回弹问题研究: [湖南大学博士学位论文].长沙:湖南大学, 2007
    [90] RF Riesenfeld. On Chaikin's algorithm. Computer Graphics and Image Processing, 1975, 4: 304-310
    [91] Hartley DJ, Judd CJ. Parametrization of beziertype B-spline curves and surfaces. CAD, 1978, 10: 130-134
    [92] John O Hallquist. LS-DYNA Theoretical Manual. USA: Livermore Software Technology Corporation, 1998
    [93] Hill R. The Mathematical Theory of Plasticity. Clarendon Press. Oxford, 1950
    [94] Fuh-Kou Chen and Pao-Ching Tszeng. An analysis of drawbead restraining force in the stamping process, International Journal of Machine Tools & Manufature, 1998, 38(7): 827-842
    [95] Stoughton T B. Model of drawbead forces in sheet metal forming. Proceedings of the 15th IDDRG, Dearborn, USA and Toronto, Canada, 1988, 205-215
    [96]王勖成,邵敏.有限单元法基本原理和数值方法.第2版.北京:清华大学出版社, 1997, 483-527
    [97] Hill R. A theory of the yielding and plastic flow of anisotropic materials. Proceedings of the Royal Society of London, Series A, 1948, 193: 281-297
    [98] Hill R. Theoretical plasticity of textured aggregates. Mathematical Proceedings of Cambridge Philosophical Society, 1979, 85: 179-191
    [99]李东升,黄小明,胡世光.汽车覆盖件成型中拉延筋约束力的模拟计算.塑性工程学报, 1994, 1: 59-65
    [100] NUMISHEET’93. Proceedings of the 2nd international conference of numerical simulation of 3-D sheet metal forming processes. Isehara, Japan, 1993
    [101]聂昕.汽车板件的回弹相关问题研究: [湖南大学博士学位论文].长沙:湖南大学, 2008
    [102] Onate E, Rojeck J, Garino C G. NUMISTAMP A research project for assessment of finite element models for stamp processes. Journal of Materialsprocessing Technology, 1995, 50(1): 17-38
    [103]殷有泉,固体力学非线性有限元引论,北京大学出版社, 1987
    [104] T J R HUGHES, W K LIU. Nonlinear finite element analysis of shell: partI. Three-dimensional shells. Computer Methods in Applied Mechanics and Engineering, 1981, 26: 331-362
    [105] HUGHES T J R, LIU W K. Nonlinear finite element analysis of shells-part II Two-dimensional shells. Computer Methods in Applied Mechanics and Engineering, 1981, 27: 167-181
    [106] Teb Belytschko, Jerry I Lin, Chen-Shyh Tsay. Explicit algorithms for the nonlinear dynamics of shell. Computer Methods in Applied Mechanics and Engineering, 1984, 42: 225-251
    [107] Xu W L, Ma C H, Li C H, et al. Sensitive factors in springback simulation for sheet metal forming. Journal of Materials Processing Technology, 2004, 151(1-3): 217-222
    [108] Li K P, Carden W P, Wagoner R H. Simulation of springback. International Journal of Mechanical Sciences, 2002, 44(1): 103-122
    [109] Lee S W, Yang D Y. An assessment of numerical parameters influencing springback in explicit finite element analysis of sheet metal forming process. Journal of Materials Processing Technology, 1998, (80–81): 60-67
    [110] Jody Shaw, Kenichi Watanabe, Ming Chen. Metal Forming Characterization and Simulation of Advanced High Strength Steels. SAE 2001-01-1139, 1-10
    [111]赵军,苏春建,官英平,等. U形件弯曲影响回弹因素模拟分析.锻压技术, 2007, 32(6): 136-140
    [112]刘文卿.试验设计.北京:清华大学出版社, 2005
    [113]张铁茂,丁建国.试验设计与数据处理.兵器工业出版社, 1990
    [114] Lindman H R. Analysis of variance in experimental design. New York: Springer-Verlag, 1991
    [115] Karafillis A P, Boyce M C. Tooling and binder design for sheet metal forming processes compensating springback error. Int J Mech Tools Manufact, 1996, 36 (4): 503-526
    [116]李延平,朱东波,卢秉恒.基于RP/RT/RE技术的金属板料冲压成形回弹误差补偿系统.中国机械工程, 2005, 7: 636-640
    [117] PARK D W, KANG J J, HONG J P. Springback simulation by combination method of explicit and implicit FEM. Proceedings of Numisheet’99, September 13-17, 1999. University of Franche-Comte and ENSMM Besancon.Besancon, France: J. C. Gelin, 1999, 35-40
    [118] HU Shimin, LI Youfu. Modifying the shape of NURBS surface with geometric constraints. Computer Aided Design, 2001, 33(12): 903-912
    [119] Hang Shawn Cheng, Jian Cao, Cedric Xia Z. An accelerated springback compensation method. International Journal of Mechanical Sciences, 2007, 49: 267-279

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