填隙补偿对碳纤维/环氧树脂复合材料-铝合金装配结构力学性能的影响

叶鑫; 安鲁陵; 岳烜德; 高国强

doi:10.13801/j.cnki.fhclxb.20191207.002

填隙补偿对碳纤维/环氧树脂复合材料-铝合金装配结构力学性能的影响

doi: 10.13801/j.cnki.fhclxb.20191207.002

南京航空航天大学　江苏省精密与微细制造技术重点实验室，南京 210016

基金项目: 国家自然科学基金(51975280)；国家商用飞机制造工程技术研究中心项目(COMAC-SFGS-2018-3008)

详细信息

通讯作者:
安鲁陵，博士，教授，博士生导师，研究方向为飞机装配技术　E-mail：anllme@nuaa.edu.cn

中图分类号: TB332
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出版历程
- 收稿日期: 2019-10-23
- 录用日期: 2019-12-02
- 网络出版日期: 2019-12-09
- 刊出日期: 2020-09-15

Effect of gap-filling compensation on mechanical properties of carbon fiber/epoxy composite-aluminum assembly structure

Jiangsu Key Laboratory of Precision and Micro-manufacturing Technology, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China

摘要

摘要: 碳纤维/环氧树脂复合材料和铝合金作为主要的航空材料，在飞机结构中存在着大量装配关系，但受成型工艺方法的限制，两种材料在制造和装配偏差的情况下，构件配合面间会产生装配间隙，当间隙超过一定大小时，需要采取填隙补偿措施。本研究基于实际结构抽象出碳纤维/环氧树脂复合材料-铝合金装配模型，使用装配试验台模拟施加螺栓预紧力，通过应变片实验比较强迫装配及垫片补偿情况下试件局部表面的应变分布，结合三维数字图像相关(3D-DIC)实验测得的试件表面应变场分析变形规律；通过有限元进行层间应力分析，提取内聚力单元各应力分量和损伤情况，研究填隙补偿对碳纤维/环氧树脂复合材料层间应力和局部损伤的影响。结合实验和仿真分析结果表明：强迫装配时，碳纤维/环氧树脂复合材料-铝合金试件主要受弯曲变形和螺栓头挤压的影响，且随着装配间隙的增大，各应变值均增大；垫片补偿在改善弯曲变形引起的应变状态的同时，也使中间贴合部位的螺栓头挤压区应变增大，但总体而言，垫片的引入使碳纤维/环氧树脂复合材料-铝合金试件表面应变分布趋于均匀，降低了碳纤维/环氧树脂复合材料损伤情况，且液体垫片补偿效果略好于可剥垫片。
- 飞机装配 /
- 填隙补偿 /
- 三维数字图像相关(3D-DIC) /
- 有限元 /
- 液体垫片 /
- 可剥垫片
Abstract: As main aviation materials, there are a lot of assembly relationships between carbon fiber/epoxy composites and aluminum in aircraft structures. However, due to limitation of the composite forming process, assembly gaps will be created between the mating surfaces in the case of manufacturing and assembly deviations. When the gap exceeds a certain size, gap-filling compensation is necessary. Based on the actual structure, the carbon fiber/epoxy composite-aluminum assembly model was abstracted, the assembly test bench was used to simulate the pre-tightening force of the bolt, and the strain gauge and 3D digital image correlation(3D-DIC) experiment were used to compare the strain on the surface under the condition of forced assembly and gap-filling compensation in older to analyze the deformation rule of the component. The interlaminar stress analysis was carried out by finite element method, and the effects of gap-filling compensation on the interlaminar stress and local damage of the carbon fiber/epoxy composite-aluminum assembly structure were studied by extracting the stress components and damage of the cohesive element. The results of experimental and simulation analysis show that with the assembly gap increasing, the strain values increase; Gap-filling compensation improves the strain state caused by the bending deformation, while the strain of the bolt head extrusion zone is also increased. In general, gap-filling compensation makes the strain distribution more uniform and reduces damage of the carbon fiber/epoxy composite, and the liquid shim effect is slightly better than the peelable shim.
- aircraft assembly /
- gap-filling compensation /
- 3D digital image correlation(3D-DIC) /
- finite element /
- liquid shim /
- peelable shim

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图 1 复合材料翼盒

Figure 1. Composite wing box

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图 2 复合材料-铝合金装配间隙简化模型示意图

Figure 2. Schematic diagram of simplified model of composite-aluminum assembly gap

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图 3 高锁螺栓预紧力加载实验装置

Figure 3. Experimental device for preloading high-lock bolts

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图 4 施加垫片试样

Figure 4. Specimens with shim

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图 5 复合材料和铝合金试件尺寸及应变片布置

Figure 5. Size of composite and aluminum specimens and arrangement of strain gauges

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图 6 三维数字图像相关(3D-DIC)操作系统

Figure 6. Operating system of 3D digital image correlation(3D-DIC)

A—CCD cameras; B—Light source; C—Specimen

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图 7 EA9394液体垫片的应力-应变曲线^[18]

Figure 7. Stress-strain curve of EA9394 liquid shim^[18]

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图 8 碳纤维/环氧树脂复合材料-铝合金装配有限元模型

Figure 8. Finite element model of carbon fiber/epoxy composite-aluminum assembly

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图 9 碳纤维/环氧树脂复合材料-铝合金装配有限元模型边界条件

Figure 9. Finite element model with boundary conditions of carbon fiber/epoxy resin composite-aluminum assembly

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图 10 内聚力单元示意图

Figure 10. Diagram of cohesion element

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图 11 碳纤维/环氧树脂复合材料-铝合金无装配间隙时各测点变形情况

Figure 11. Deformation of each measuring point of carbon fiber/epoxy composite-aluminum without assembly gap

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图 12 3D-DIC应变分析区

Figure 12. Strain analysis area of 3D-DIC

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图 13 碳纤维/环氧树脂复合材料-铝合金无装配间隙下全场应变云图

Figure 13. Full-field strain nephogram of carbon fiber/epoxy composite-aluminum without assembly gap

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图 14 碳纤维/环氧树脂复合材料-铝合金强迫装配时各测点应变

Figure 14. Strain of each measuring point of carbon fiber/epoxy composite-aluminum with forced assembly

Al—Aluminum; Composite—Carbon fiber/epoxy composite; no—Forced assembly; 1, 2, 3, 4—Measuring point

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图 15 碳纤维/环氧树脂复合材料-铝合金强迫装配对各测点变形的影响

Figure 15. Effect of forced assembly on deformation of each measuring point of carbon fiber/epoxy composite-aluminum

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图 16 碳纤维/环氧树脂复合材料-铝合金强迫装配下测点1和3应变片与3D-DIC测量值对比

Figure 16. Comparison of measured values of strain gauges and 3D-DIC at points 1 and 3 of carbon fiber/epoxy composite-aluminum under forced assembly

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图 17 碳纤维/环氧树脂复合材料-铝合金强迫装配时试件表面全场应变云图

Figure 17. Full-field strain nephogram of carbon fiber/epoxy composite-aluminum under forced assembly

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图 18 碳纤维/环氧树脂复合材料-铝合金填隙补偿下各测点应变

Figure 18. Strain of each measuring point of carbon fiber/epoxy composite-aluminum under gap-filling compensation

lq—Liquid shim; pe—Peelable shim

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图 19 碳纤维/环氧树脂复合材料-铝合金在2.0 mm装配间隙下e_xx应变云图

Figure 19. e_xx strain nephogram of carbon fiber/epoxy composite-aluminum at 2.0 mm gap

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图 20 碳纤维/环氧树脂复合材料-铝合金在2.0 mm装配间隙下e_yy应变云图

Figure 20. e_yy strain nephogram of carbon fiber/epoxy composite-aluminum at 2.0 mm gap

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图 21 碳纤维/环氧树脂复合材料的3D-DIC全场应变云图和有限元仿真应变云图

Figure 21. Full-field strain nephogram of 3D-DIC and finite element model(FEM) of carbon fiber/epoxy composite

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图 22 碳纤维/环氧树脂复合材料填隙补偿下各应力峰值变化曲线

Figure 22. Peak stress curves of carbon fiber/epoxy composite under gap-filling compensation

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图 23 碳纤维/环氧树脂复合材料无装配间隙下内聚力单元应力分布及损伤情况

Figure 23. Stress distribution and damage of cohesive element of carbon fiber/epoxy composite without assembly gap

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图 24 碳纤维/环氧树脂复合材料填隙补偿下内聚力单元应力分布及损伤情况

Figure 24. Stress distribution and damage of cohesive element of carbon fiber/epoxy composite under gap-filling compensation

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表 1 碳纤维/环氧树脂复合材料和可剥垫片的性能参数^{[13, 29]}

Table 1. Performance parameters of carbon fiber/epoxy composite and peelable shim^{[13, 29]}

Material	E₁₁/GPa	E₂₂/GPa	E₃₃/GPa	G₁₂/GPa	G₁₃/GPa	G₂₃/GPa	ν₁₂	ν₁₃	ν₂₃
Carbon fiber/epoxy composite	156.0	8.35	8.35	4.20	4.20	2.52	0.33	0.33	0.55
Peelable shim	20.1	20.10	8.10	3.30	3.30	3.30	0.18	0.18	0.18
Notes: E₁₁, E₂₂, E₃₃—Young’s modulus; G₁₂, G₁₃, G₂₃—Shear modulus; ν₁₂, ν₁₃, ν₂₃—Poisson’s ratio.

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表 2 内聚力单元属性

Table 2. Properties of cohesive element

K_n/(10⁵ N·mm⁻³)	K_s=K_t/(10⁵ N·mm⁻³)	G_n/(N·mm⁻¹)	G_s =G_t/(N·mm⁻¹)	t_n/MPa	t_s=t_t/MPa
1	1	0.352	1.45	60	80
Notes: K_n—Normal modulus; K_s, K_t—Tangential modulus; G_n,G_s,G_t—Fracture energy of mode Ⅰ, Ⅱ, Ⅲ, respectively; t_n—Normal strength; t_s, t_t—Tangential strength.

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表 3 碳纤维/环氧树脂复合材料-铝合金无装配间隙时各测点实验应变片测量值

Table 3. Measurement of experimental strain gauges at each measuring point of carbon fiber/epoxy composite-aluminum without assembly gap

Measuring point	1	2	3	4
Carbon fiber/ epoxy composite	−436.8	601.8	393.7	−337.4
Aluminum	−181.5	142.5	245.1	−248.9

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表 4 碳纤维/环氧树脂复合材料-铝合金无间隙时测点1和3应变片与3D-DIC测量值对比

Table 4. Strain comparison of measured values of strain gauges and 3D-DIC at points 1 and 3 of carbon fiber/epoxy composite-aluminum under no-gap conditions

Measuring method	Strain gauge		3D-DIC
Measuring point	1	3	e_xx	e_yy
Carbon fiber/ epoxy composite	−436.8	393.7	−444.5	399.3
Aluminum	−181.5	245.1	−180.9	229.4

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表 5 碳纤维/环氧树脂复合材料-铝合金在0.2 mm和2.0 mm装配间隙下各测点应变片测量值

Table 5. Measurements of strain gauges at each points of carbon fiber/epoxy composite-aluminum with gaps of 0.2 mm and 2.0 mm

Measuring point	Gap/mm	Strain of aluminum/10^–6			Strain of composite/10^–6
Measuring point	Gap/mm	Forced assembly	Liquid shim	Peelable shim	Forced assembly	Liquid shim	Peelable shim
1	0.2	−500.4	−200.9	−365.5	−733.1	−681.3	−729.8
1	2.0	−5 059.6	−1 469.5	−1 300.9	−7 140.8	−1 974.1	−2 389.5
2	0.2	−200.9	126.4	229.4	281.8	613.9	723.8
2	2.0	−2 370.4	444.5	337.4	−1 842.9	903.5	1 914.2
3	0.2	304.1	293.4	377.4	419.5	569.3	748.1
3	2.0	975.9	811.9	525.3	1 744.7	1 363.9	1 999.8
4	0.2	−236.9	−273.8	−326.4	−598.6	−451.5	−612.4
4	2.0	−845.9	−495.1	−1 233.7	−2 535.9	−1 276.1	−3 473.1

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参考文献(31)

[1]	李东升, 翟雨农, 李小强. 飞机复合材料结构少无应力装配方法研究与应用进展[J]. 航空制造技术, 2017(9):30-34. LI D S, ZHAI Y N, LI X Q. Research and application advances of stress-less assembly methods forcomposite airframe[J]. Aeronautical Manufacturing Technology,2017(9):30-34(in Chinese).
[2]	邢丽英, 包建文, 礼嵩明, 等. 先进树脂基复合材料发展现状和面临的挑战[J]. 复合材料学报, 2016, 33(7):1327-1338. XING L Y, BAO J W, LI S M, et al. Development status and facing challenge of advanced polymer matrix composites[J]. Acta Materiae Compositae Sinica,2016,33(7):1327-1338(in Chinese).
[3]	COLEMAN R M. The effects of design, manufacturing processes and operations management on the assembly of aircraft composite structure[D]. Massachusetts: Massachusetts Institute of Technology, 1991.
[4]	杜善义. 先进复合材料与航空航天[J]. 复合材料学报, 2007, 24(1):1-12. doi: 10.3321/j.issn:1000-3851.2007.01.001 DU S Y. Advanced composite materials and aerospace engineering[J]. Acta Materiae Compositae Sinica,2007,24(1):1-12(in Chinese). doi: 10.3321/j.issn:1000-3851.2007.01.001
[5]	赵稼祥. 碳纤维复合材料在民用航空上的应用[J]. 高科技纤维与应用, 2003, 28(3):1-4, 35. ZHAO J X. Application of carbon composite materials for civil aviation[J]. Hi-Tech Fiber <italic>&</italic> Application,2003,28(3):1-4, 35(in Chinese).
[6]	MARSH G. Airbus A350 XWB update[J]. Reiforced Plastics,2010,54(6):20-24. doi: 10.1016/S0034-3617(10)70212-5
[7]	Department of Defense. Composite materials handbook Volume 1: Polymer matrix composites guidelines for characterization of structural materials[M]. Washington: Department of Defense, 2002.
[8]	STEINBERG M A. Net shape technology in aerospace structures volume 4: Future composite manufacturing technology[M] Washington: National Research Council, 1986.
[9]	CAMPBELL F C. Manufacturing processes for advanced composites[M]. Amsterdam: Elsevier, 2004.
[10]	徐福泉, 高大伟. 复合材料结构装配过程中的制孔和连接[J]. 航空制造技术, 2010(17):72-74. doi: 10.3969/j.issn.1671-833X.2010.17.015 XU F Q, GAO D W. Drilling and linking during composites structure assembly process[J]. Aeronautical Manufacturing Technology,2010(17):72-74(in Chinese). doi: 10.3969/j.issn.1671-833X.2010.17.015
[11]	张桂书. 飞机复合材料构件装配间隙补偿研究[D]. 南京: 南京航空航天大学, 2015. ZHANG G S. Research on assembly gap compensation for aircraft composite components[D]. Nanjing: Nanjing University of Aeronautics and Astronautics, 2015(in Chinese).
[12]	云一珅. 填隙补偿参数对复材螺栓连接结构的力学性能的影响研究[D]. 南京: 南京航空航天大学, 2017. YUN Y S. Research on the effect of gap-filling parameters on mechanical behavior of the bolt connected composite structure[D]. Nanjing: Nanjing University of Aeronautics and Astronautics, 2017 (in Chinese).
[13]	岳烜德, 安鲁陵, 云一珅, 等. 液体垫片对复合材料装配结构应力和应变的影响[J]. 复合材料学报, 2018, 35(10):2665-2677. YUE X D, AN L L, YUN Y S, et al. Influences of the liquid shim on the mechanical properties of single-lap composite bolted joint[J]. Acta Materiae Compositae Sinica,2018,35(10):2665-2677(in Chinese).
[14]	ATTAHU C Y, AN L L. Influence of assembly gap and shims on the strain and stress of bolted composite-aluminum structures[J]. ARPN Journal of Engineering and Applied Sciences,2017,12(5):1593-1617.
[15]	DHÔTE J X, COMER A J, STANLEY W F, et al. Investigation into compressive properties of liquid shim for aerospace bolted joints[J]. Composite Structures,2014,109:224-230.
[16]	HÜHNE C, ZERBST A K, KUHLMANN G, et al. Progressive damage analysis of composite bolted joints with liquid shim layers using constant and continuous degradation models[J]. Composite Structures,2010,92(2):189-200. doi: 10.1016/j.compstruct.2009.05.011
[17]	COMER A J, DHÔTE J X, STANLEY W F, et al. Thermo-mechanical fatigue analysis of liquid shim in mechanically fastened hybrid joints for aerospace applications[J]. Composite Structures,2012,94(7):2181-2187. doi: 10.1016/j.compstruct.2012.01.008
[18]	LIU L. The influence of the substrate’s stiffness on the liquid shim effect in composite-to-titanium hybrid bolted joints[J]. Proceedings of the Institution of Mechanical Engineers Part G: Journal of Aerospace Engineering,2014,228(3):470-479.
[19]	PAUL D, KELLY L, VENKAYYA V. Evolution of U. S. military aircraft structures technology[J]. Journal of Aircraft,2002,39(1):18-29. doi: 10.2514/2.2920
[20]	GOERING J, BOHLMANN R E, WANEHAL S, et al. Assembly Induced delamination in composite structures[C]//Proceedings of ninth DoD/NASA/FAA Conference on Fibrous Composites in Structural Design. Lake Tahoe: NASA, 1992.
[21]	CAMPONESCHI E T, BOHLMANN R E, FOGARTY J H. Composite to metal joints for the ARPA man-rated demonstration article[J]. Journal of Thermoplastic Composite Materials,1995,8(1):56-79.
[22]	肖睿恒, 云一珅, 胡坚皓, 等. 一种用于复合材料结构装配填隙补偿分析的方法和装置: 中国, CN108507764A[P]. 2018-09-07. XIAO R H, YUN Y S, HU J H, et al. A method and device for gap-filling compensation analysis of composite structure assembly: China, CN108507764A[P]. 2018-09-07(in Chinese).
[23]	THOPPUL S D, FINEGAN J, GIBSON R F. Mechanics of mechanically fastened joints in polymer-matrix composite structures: A review[J]. Composites Science <italic>&</italic> Technology,2009,69(3-4):301-329.
[24]	BRESSON G, JUMEL J, SHANAHAN M E R, et al. Statistical aspects of the mechanical behaviour a paste adhesive[J]. International Journal of Adhesion <italic>&</italic> Adhesives,2013,40(1):70-79.
[25]	谢鸣九. 复合材料连接[M]. 上海: 上海交通大学出版社, 2011. XIE M J. Joints for composites materials[M]. Shanghai: Shanghai Jiaotong University Press, 2011(in Chinese).
[26]	ASTM International. Standard test method for bearing response of polymer matrix composite laminates: ASTM D5961M—17[S]. West Conshohocken: ASTM International, 2017.
[27]	部标准编制组. 部标准《高锁螺栓、螺母》介绍[J]. 航空标准化与质量, 1981(3):1-4. Department Standard Establishment Group. The standard of high lock bolt and nut[J]. Aeronautic Standardization <italic>&</italic> Quality,1981(3):1-4(in Chinese).
[28]	KAPIDŽIĆ Z, NILSSON L, ANSELL H. Finite element modeling of mechanically fastened composite-aluminum joints in aircraft structures[J]. Composite Structures,2014,109:198-210.
[29]	ZHAI Y N, LI X Q, WANG L, et al. Three-dimensional layer-by-layer stress analysis of single-lap, countersunk composite joints with varying joining interface conditions[J]. Composite Structures,2018,202:1021-1031.
[30]	MCCARTHY M A, MCCARTHY C T, LAWLOR V P, et al. Three-dimensional finite element analysis of single-bolt, single-lap composite bolted joints Part I: Model development and validation[J]. Composite Structures,2005,71(2):159-175.
[31]	ATAS A, SOUTI C. Strength prediction of bolted joints in CFRP composite laminates using cohesive zone elements[J]. Composites Part B: Engineering,2014,58:25-34. doi: 10.1016/j.compositesb.2013.10.017