Journal of Jilin University(Engineering and Technology Edition) ›› 2021, Vol. 51 ›› Issue (1): 139-146.doi: 10.13229/j.cnki.jdxbgxb20191063

Previous Articles    

Residual strength prediction of adhesive CFRP-aluminum alloy adhesively bonded joint based on FTIR analysis

Wen-long MU1,2(),Jing-xin NA1(),Wei TAN1,Guang-bin WANG1,Hao SHEN1,Jian-ze LUAN1   

  1. 1.State Key Laboratory of Automotive Simulation and Control，Jilin University，Changchun 130022，China
    2.College of Mechnical and Electrical Engineering，Henan Agricultural University，Zhengzhou 450002，China
  • Received:2019-09-27 Online:2021-01-01 Published:2021-01-20
  • Contact: Jing-xin NA E-mail:muwl1992@hotmail.com;najingxin@jlu.edu.cn

RICH HTML

 2   

PDF (PC)

247

Abstract:

The aging behavior and mechanism of adhesively bonded joints of CFRP- aluminum alloy exposured to hygrothermal environment were studied in this paper. First， the joints were aged at 80℃ with 95% relative humidity （RH） for different durations and then the quasi-static tensile and shear tests were performed. Second， the residual strength and failure mode of the joint were analyzed. Third， combined with the Fourier transform infrared spectroscopy （FTIR） results of adhesive， the aging mechanism of adhesive joints was revealed. The results indicate that the strength of joint decreases significantly due to hygrothermal aging， which approximates the exponential function. The failure modes of unaged and aged joints all presented cohesive failure primarily. However， with the increase in aging duration the adhesive-substrate interface was damaged， and the surfaces of aged joints became relatively rough due to the plasticizing of the adhesive. The hydrolysis reaction occurred in the adhesive due to hygrothermal aging， resulting in chain scission. The post curing of adhesive was also observed at the initial stage of aging. Adhesive degradation is the primary cause of the decrease in the strength of the joint. Finally a residual strength prediction method was established， which can be used to predict residual strength of hygrothermally aged joints by testing the chemical characteristics of adhesive.

Key words: carbon fiber reinforced polymer composites（CFRP）, adhesively bonded joint, hygrothermal aging, fourier transform infrared spectroscopy analysis, residual strength prediction

CLC Number: 

  • U463.82

Table 1

Mechanical properties of CFRP"

Ex/GPaEy/GPaVxyGxy/GPaGxz/GPaGyz/GPa
单向125±1210±20.077±0.62±0.52±0.3
斜纹55±555±50.134±0.52±0.32±0.3

Fig.1

Geometries and dimensions of adhesive joints"

Fig.2

Model of adhesive fixture"

Fig.3

Quasi-static testing of joints"

Fig.4

Residual strength loads of joints as a function of exposure time"

Fig.5

Representative fracture surfaces of butt joints before and after hygrothermal aging"

Fig.6

Representative fracture surfaces of shear joints before and after hygrothermal aging"

Fig.7

Representative SEM photos of fracture surfaces -×100"

Fig.8

Normalized FTIR spectrum of adhesive Araldite? 2015 with different aging times"

Table 2

Typical functional groups and corresponding wave numbers in FTIR spectra of Araldite? 2015"

波数/cm-1官能团
3325-OH、-NH伸缩振动
2923、2850烷基 (-CH3、-CH2) 伸缩振动
1736酯基 (-(C=O)-O)
1648羰基 (C=O)
1508p-二取代苯环的半圆伸缩振动
1452脂族基的C–H弯曲振动
1053醚类C-O-C反式伸缩振动
914p-亚苯基

Fig.9

Changes in absorbance intensities of functional groups as functions of the hygrothermal exposure time"

Fig.10

Pearson correlation coefficients between absorbance intensities functional groups and residual strength"

Table 3

Residual strength prediction accuracy"

波数/cm-1接头类型
对接剪切
332594.0394.19
173699.7199.70
164895.8996.03
91498.5998.67

Fig.11

Relative error of residual strength prediction"

1 胡志清, 郑会会, 徐亚男, 等. 表面微沟槽对Al/CFRP胶结性能的影响[J]. 吉林大学学报:工学版, 2018, 48(1): 229-235.
Hu Zhi-qing, Zheng Hui-hui, Xu Ya-na, et al. Effect of Al surface with micro/macro grooves on AI/CFRP adhesive-bonded joints[J]. Journal of Jilin University(Engineering and Technology Edition), 2018, 48(1): 229-235.
2 Budhe S, Banea M D, Barros S D, et al. An updated review of adhesively bonded joints in composite materials[J]. International Journal of Adhesion & Adhesives, 2017, 72: 30-42.
3 Mu W, Qin G, Na J, et al. Effect of alternating load on the residual strength of environmentally aged adhesively bonded CFRP-aluminum alloy joints[J]. Composites Part B: Engineering, 2019, 168: 87-97.
4 Viana G, Costa M, Banea M D, et al. A review on the temperature and moisture degradation of adhesive joints[J]. Journal of Materials: Design and Applications, 2017, 231(5): 488-501.
5 Lin Y C, Chen X, Zhang H J, et al. Effects of hygrothermal aging on epoxy-based anisotropic conductive film[J]. Materials Letters, 2006, 60(24): 2958-2963.
6 Xiao G Z, Shanahan M E R. Irreversible effects of hygrothermal aging on DGEBA/DDA epoxy resin[J]. Journal of Applied Polymer Science, 1998, 69(2): 363-369.
7 牛一凡, 李璋琪, 朱晓峰. 全湿热场下碳纤维/环氧树脂复合材料弯曲性能及寿命预测[J]. 复合材料学报, 2020, 37(1):104-112.
Niu Yi-fan, Li Zhang-qi, Zhu Xiao-feng. Flexural properties and life-time estimation of carbon fiber/epoxy composite under hygrothermal conditions[J]. Acta Materiae Compositae Sinica, 2020, 37(1):104-112.
8 Liu S, Cheng X, Zhang Q, et al. An investigation of hygrothermal effects on adhesive materials and double lap shear joints of CFRP composite laminates[J]. Composites Part B: Engineering, 2016, 91: 431-440.
9 Viana G, Costa M, Banea M D, et al. Moisture and temperature degradation of double cantilever beam adhesive joints[J]. Journal of Adhesion Science and Technology, 2017, 31(16): 1824-1838.
10 张欢, 许文, 邹士文, 等. 环氧胶粘剂及其胶接界面热氧老化机理研究[J]. 材料导报, 2017, 31(12): 104-108.
Zhang Huan, Xu Wen, Zou Shi-wen, et al. Thermal-oxidative aging mechanism of epoxy adhesive and its interface[J]. Materials Review, 2017, 31(12): 104-108.
11 Jana S, Zhong W H. FTIR study of ageing epoxy resin reinforced by reactive graphitic nanofibers[J]. Journal of Applied Polymer Science, 2007, 106(5): 3555-3563.
12 Cherdoud‐Chihani A, Mouzali M, Abadie M J M. Study of crosslinking AMS/DGEBA system by FTIR[J]. Journal of Applied Polymer Science, 1998, 69(6): 1167-1178.
13 Khan L A, Nesbitt A, Day R J. Hygrothermal degradation of 977-2A carbon/epoxy composite laminates cured in autoclave and Quickstep[J]. Composites Part A: Applied Science & Manufacturing, 2010, 41(8): 942-953.
14 汪冬华. 多元统计分析与SPSS应用[M]. 上海:华东理工大学出版社, 2010.
15 郇中丹, 黄海洋. 偏微分方程[M]. 北京:高等教育出版社, 2013.
16 Liljedahl C D M, Crocombe A D, Wahab M A, et al. The effect of residual strains on the progressive damage modeling of environmentally degraded joints[J]. Journal of Adhesion Science and Technology, 2005, 19(7): 525547.
[1] NA Jing-xin,MU Wen-long,FAN Yi-sa,TAN Wei,YANG Jia-zhou. Effect of hygrothermal aging on steel-aluminum adhesive joints for automotive applications [J]. Journal of Jilin University(Engineering and Technology Edition), 2018, 48(6): 1653-1660.
Viewed
Full text


Abstract

Cited
  Shared   
  Discussed   
No Suggested Reading articles found!
Copyright © Journal of Jilin University(Engineering and Technology Edition), All Rights Reserved.
Tel: +86-431-85095297　Fax: +86-431-85094074　E-mail: xbgxb@jlu.edu.cn
Powered by Beijing Magtech Co. Ltd