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Methods for Suppressing Tearing of PET Coating During Forming of VCM Steel Sheet for Fabricating Washer

세탁기용 VCM 강판 성형시 PET 코팅층 찢김 저감방법

  • Received : 2011.01.11
  • Accepted : 2011.07.04
  • Published : 2011.09.01

Abstract

A VCM sheet is a metal sheet on which PET/PVC is coated for outer panels of home appliances. The purpose of this study is to obtain methods for suppressing PET tearing that occurs during the press forming of the VCM sheet. In order to identity the factors that minimize PET tearing, an FE analysis was performed. The occurrence of PET tearing cannot be predicted using the conventional forming limit diagram. PET is torn by friction between a die and sheet, which is caused by the thickening of material at a die corner. To reduce the thickening of material, the blank shape was re-designed and the thickened material at a flange was removed by a trimming process. The results of the FE-analysis involving modified process parameters showed that the thickness of the product at a die corner is distributed within the clearance of drawing and flangeforming process. A forming experiment was conducted to verify the proposed process parameters. A good final product was obtained without PET tearing of the VCM sheet.

Keywords

Vinyl Coated Metal;PET Tearing;Flange Forming

References

  1. Ravi, V. and Jyhwen, W., 2007, "Adhesion of Coatings to Sheet Metal Under Plastic Deformation," International Journal of Adhesion & Adhesive, Vol. 27, pp. 480-492. https://doi.org/10.1016/j.ijadhadh.2006.08.003
  2. Van den Bosch, M.j., Schreurs, P.J.G., Geers, M.G.D., 2009, "On the Prediction of Delamination during Deep-drawing of Polymer Coated Metal Sheet," Journal of Materials Processing Technology, Vol. 209, pp. 297-302. https://doi.org/10.1016/j.jmatprotec.2008.02.024
  3. Van den Bosch, M.j., Schreurs, P.J.G., Geers, M.G.D., 2008, "Interfacial Characterization of Pre-strained Polymer Coated Steel by a Numerical-experimental Approach," Mechanics of Materials, Vol. 40, pp. 302-317. https://doi.org/10.1016/j.mechmat.2007.09.002
  4. Van den Bosch, M.j., Schreurs, P.J.G. and Geers, M.G.D., 2008, "Identification and Characterization of Delamination in Polymer Coated Metal Sheet," Journal of the Mechanics and Physics of Solids, Vol. 56, pp. 3259-3276. https://doi.org/10.1016/j.jmps.2008.07.006
  5. Van Tijum, R., Vellinga, W.P., De Hosson, J.Th.M., 2007, "Surface Roughening of Metal-Polymer Systems During Plastic Deformation," Acta Materialia, Vol. 55, pp. 2757-2764. https://doi.org/10.1016/j.actamat.2006.12.013
  6. Van Tijum, R., De jong, B.V.C., Vellinga, W.P., De Hosson, J.Th.M., 2007, "In-situ Birefringence Microscopy of Uniaxially Stretched Metal-polymer Laminate," Surface & Coatings Technology, Vol. 201, pp.4633-4639. https://doi.org/10.1016/j.surfcoat.2006.10.002
  7. Lee, C. J., Lee, S. K., Ko, D. C. and Kim B. M., 2009, "Evaluation of Adhesive Properties using Cohesive Zone Model," Trans. of the KSME(A), Vol. 33, No. 5, pp. 474-481. https://doi.org/10.3795/KSME-A.2009.33.5.474
  8. Kim, H. Y., Choi, C. H. and Bae, W. B., 1999, "Study for Friction Characteristics of Pre-coated Metal," Journal of the Korean Society of Precision Engineering, 1999 spring Conference, pp. 1010-1013.
  9. Kim, D. H., Kim, B. M., 2001, "Formability of Non- Vinyl Pre-coated Metal Sheet," Journal of the Korean Society of Precision Engineering, Vol. 18, No. 4, pp. 121-128.
  10. 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," Journal of Materials Processing Technology, Vol. 209, pp. 297-302. https://doi.org/10.1016/j.jmatprotec.2008.02.024
  11. Ko, D. C., Cha, S. H., Lee, S. K., Lee, C. J. and Kim, B. M., 2010, "Application of a Feasible Formability Diagram for the Effective Design in Stamping Processes of Automotive Panels," Materials and Design, Vol. 31, pp. 1262-1275. https://doi.org/10.1016/j.matdes.2009.09.022