DOI QR코드

DOI QR Code

Delamination Limit of Aluminum Foil-Laminated Sheet During Stretch Forming

등이축인장 모드 변형시 알루미늄 포일 접착강판의 박리한계 예측

  • Lee, Chan-Joo (School of Mechanical Engineering, Pusan Nat'l Univ.) ;
  • Son, Young-Ki (School of Mechanical Engineering, Pusan Nat'l Univ.) ;
  • Lee, Jung-Min (Dongnam Regional Division, Korea Institute of Industrial Technology) ;
  • Lee, Seon-Bong (Faculty of Mechanical and Automotive Engineering, Keimyung Univ.) ;
  • Byun, Sang-Deog (LG Electronics) ;
  • Kim, Byung-Min (School of Mechanical Engineering, Pusan Nat'l Univ.)
  • Received : 2011.09.19
  • Accepted : 2022.01.25
  • Published : 2012.04.01

Abstract

An aluminum foil-laminated sheet is a laminated steel sheet on which aluminum foil is adhesively bonded. It is usually used on the outer panel of home appliances to provide an aluminum feeling and appearance on the surface of the product. The delamination of aluminum foil is one of the main problems during the stretch forming process. The purpose of this study is was to determine the delamination limit of an aluminum foil-laminated sheet in the stretch forming process. The delamination was dependent on the bonding strength between aluminum foil and steel sheet. The fracture behavior of the interface between the aluminum foil and the steel sheet was described by a cohesive zone model. A finite element was conducted with the cohesive zone model to analyze the relationship between the delamination limit and the bonding strength of the interface. The interface bonding strength was evaluated by lap shear and T-peel test. The delamination limit of the aluminum foil-laminated sheet was determined by using the bonding strength of the steel sheet. The delamination limit was also verified by the Erichsen test.

알루미늄 포일 접착강판은 접착제를 이용하여 알루미늄 포일을 드로잉용 GI 강판 위에 접착시킨 강판이다. 알루미늄 포일의 박리현상은 알루미늄 포일 강판의 주된 성형불량 중의 하나이다. 본 연구에서는 가전제품의 외관에 활용되는 알루미늄 포일 접착강판의 박리한계를 규명하였다. 알루미늄 포일 접착강판의 박리는 알루미늄 포일과 강판의 접착강도에 의해 결정된다. 알루미늄 접착강판의 박리와 접착강도와의 관계를 분석하기 위해 CZM 을 활용하여 알루미늄 포일 접착강판의 계면접착력에 따른 알루미늄 포일 박리변형률의 변화를 분석하였다. 해석결과, 박리발생의 주원인은 강판의 변형 중 접착계면에서 발생하는 전단응력에 의해 박리가 발생함을 확인하였다. 또한 알루미늄 포일 접착강판의 계면접착력을 측정하여 강판의 등이축인장모드인 스트레치 변형에 따른 박리가 발생하는 한계변형률을 도출하였다. 도출된 알루미늄 포일 접착강판의 박리 한계는 에릭슨 시험을 통해 검증하였다.

Keywords

References

  1. Kim, D.H. and Kim, B.M., 2001, "Formability of Non-Vinyl Pre-coated Metal Sheet," J.of KSPE, Vol. 18, No. 4, pp. 123-128.
  2. Kim, C.W., Song, S.H. and Oh, D.J., 2004, "Development of the Delamination Evaluation Parameters(I) - The Delamination Aspect Ratio and the Delamination Shape Factors," J. Mech. Sci. Technol., Vol. 18, No. 11, pp. 1932-1940.
  3. van den Bosch, M.J., Schreurs, P.J.G. and Geers, M.G.D., 2009, "On the Prediction of Delamination During Deep- Drawing of Polymer Coated Metal Sheet," J. Mater. Proces. Technol., Vol. 209, pp.297-302 https://doi.org/10.1016/j.jmatprotec.2008.02.024
  4. Vayeda, R. and Wang, J., 2007, "Adhesion of Coating to Sheet Metal Under Plastic Deformation," Int. J. Adhes. Adhes., Vol. 27, pp. 480-492. https://doi.org/10.1016/j.ijadhadh.2006.08.003
  5. Chang, T., Sproat, E.A., Lai, Y.H., Shephard, N.E. and Dillard, D.A., 1997, "A Test Method for Accelerated Humidity Conditioning and Estimation of Adhesive Bond Durability," Int. J. Adhes. Adhes., Vol. 60, pp. 153-162.
  6. Dillard, D.A., Chen, B., Chang, T. and Lai, Y.H., 1999, "Analysis of the Notched Coating Adhesion Test," Int. J. Adhes. Adhes., Vol. 69, pp. 99-120.
  7. Choi, S.H., Ha, S.Y. and Kim, K.T., 2009, "Analysis for Fracture Characteristics of Porous Materials by Using Cohesive Zone Model," Trans. of KSME(A), Vol. 33, No. 6, pp.552-559.
  8. Lee, S.C. and Kim, K.T., 2008, "Deformation of the Rubber Mold by Using the Cohesive Zone Model under Cold Isostatic Pressing," Trans. of KSME(A), Vol. 32, No. 5, pp. 387-395. https://doi.org/10.3795/KSME-A.2008.32.5.387
  9. Benzeggagh, M.L. and Kenane, M., 1996, "Measurement of Mixed-Mode Delamination Fracture Toughness of Unidirectional Class/Epoxy Composites with Mixed-Mode Bending Apparatus," Compos. Sci. Technol., Vol. 56, pp. 439-449. https://doi.org/10.1016/0266-3538(96)00005-X
  10. ASTM D1876, 2002, Standard Test Method for Peel Resistance of Adhesive, American Society for Testing and Materials.
  11. ASTM D1002, 2002, Standard Test Method for Apparent Shear Strength of Single-Lap-Joint Adhesively Bonded Metal Specimens by Tension Loading, American Society for Testing and Materials.
  12. Lee, C.J., Lee, S.K., Ko, D.C. and Kim, B.M., 2009, Evaluation of Adhesive Properties Using Cohesive Zone Model : Mode I, Trans. of KSME(A), Vol. 33, No. 5, pp. 474-481. https://doi.org/10.3795/KSME-A.2009.33.5.474