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Effect of vibration transmission direction in ultrasonic thermoforming on the formability of micro-corrugations

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Abstract

The energy of ultrasonic vibrations has been used in various polymer fabrication processes owing to its rapid and energy-efficient heating capability. This study concerns ultrasonic thermoforming of micro-speaker diaphragms, especially investigating the effect of the direction of vibration transmission to improve the forming accuracy of micro-corrugations; direct and indirect ultrasonic thermoforming processes were compared thereby. Experimental comparison reveals that indirect ultrasonic thermoforming shows better heating capability and formability than direct ultrasonic thermoforming does. This indirect thermoforming was then further investigated to find optimal forming condition, with the aid of response surface analysis. By applying the optimal forming condition, the micro-speaker diaphragm could be successfully fabricated with an excellent forming ratio (> 90%), within 10 seconds cycle time. The sound quality of the developed diaphragm was as good as that of conventional diaphragms fabricated by the conventional thermoforming process, which required more than 100 seconds cycle time.

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References

  1. Sackmann, J., Burlage, K., Gerhardy, C., Memering, B., Liao, S., and Schomburg, W., “Review on Ultrasonic Fabrication of Polymer Micro Devices,” Ultrasonics, Vol. 56, pp. 189–200, 2015.

    Article  Google Scholar 

  2. Daniels, H. P. C., “Ultrasonic Welding,” Ultrasonics, Vol. 3, No. 4, pp. 190–196, 1965.

    Article  Google Scholar 

  3. Benatar, A., Eswaran, R. V., and Nayar, S. K., “Ultrasonic Welding of Thermoplastics in the Near-Field,” Polymer Engineering & Science, Vol. 29, No. 23, pp. 1689–1698, 1989.

    Article  Google Scholar 

  4. Benatar, A. and Cheng, Z., “Ultrasonic Welding of Thermoplastics in the Far-Field,” Polymer Engineering & Science, Vol. 29, No. 23, pp. 1699–1704, 1989.

    Article  Google Scholar 

  5. Liu, S. J. and Dung, Y. T., “Hot Embossing Precise Structure Onto Plastic Plates by Ultrasonic Vibration,” Polymer Engineering & Science, Vol. 45, No. 7, pp. 915–925, 2005.

    Article  Google Scholar 

  6. Mekaru, H., Goto, H., and Takahashi, M., “Development of Ultrasonic Micro Hot Embossing Technology,” Microelectronic Engineering, Vol. 84, No. 5, pp. 1282–1287, 2007.

    Article  Google Scholar 

  7. Mekaru, H., Goto, H., and Takahashi, M., “Development of Ultrasonic Micro Hot Embossing Technology,” Microelectronic Engineering, Vol. 84, No. 5, pp. 1282–1287, 2007.

    Article  Google Scholar 

  8. Michaeli, W., Kamps, T., and Hopmann, C., “Manufacturing of Polymer Micro Parts by Ultrasonic Plasticization and Direct Injection,” Microsystem Technologies, Vol. 17, No. 2, pp. 243–249, 2011.

    Article  Google Scholar 

  9. Sacristan, M., Planta, X., Morell, M., and Puiggali, J., “Effects of Ultrasonic Vibration on the Micro-Molding Processing of Polylactide,” Ultrasonics Sonochemistry, Vol. 21, No. 1, pp. 376–386, 2014.

    Article  Google Scholar 

  10. Bae, H. and Park, K., “Design and Analysis of Ultrasonic Horn for Polymer Sheet Forming,” Int. J. Precis. Eng. Manuf.-Green Tech., Vol. 3, No. 1, pp. 49–54, 2016.

    Article  Google Scholar 

  11. Bae, H.-J., Lee, H.-J., and Park, K., “Ultrasonic Assisted Thermoforming for Rapid Fabrication of a Microspeaker Diaphragm,” Microsystem Technologies, pp. 1–10, 2015. (DOI: 10.1007/s00542-015-2740-z)

    Google Scholar 

  12. Mekaru, H. and Takahashi, M., “Ultrasonic Nanoimprint on Poly (Ethylene Terephthalate) at Room Temperature,” Japanese Journal of Applied Physics, Vol. 47, No. 6S, pp. 5178–5184, 2008.

    Article  Google Scholar 

  13. Seo, Y.-S. and Park, K., “Direct Patterning of Micro-Features on a Polymer Substrate Using Ultrasonic Vibration,” Microsystem Technologies, Vol. 18, No. 12, pp. 2053–2061, 2012.

    Article  Google Scholar 

  14. Jung, W., Lee, H.-J., and Park, K., “Investigation of Localized Heating Characteristics in Selective Ultrasonic Imprinting,” Int. J. Precis. Eng. Manuf., Vol. 16, No. 9, pp. 1999–2004, 2015.

    Article  Google Scholar 

  15. Throne, J., “Technology of Thermoforming,” Hanser, New York, 1996.

    Book  Google Scholar 

  16. Hosseini, H., Berdyshev, B. V., and Mehrabani-Zeinabad, A., “Modeling of Deformation Processes in Vacuum Thermoforming of a Pre-Stretched Sheet,” Polymer-Plastics Technology and Engineering, Vol. 45, No. 12, pp. 1357–1362, 2006.

    Article  Google Scholar 

  17. Kim, D.-C. and Jeong, H.-Y., “An Optimal Design of the Internal Space in a Micro-Speaker Module,” Int. J. Precis. Eng. Manuf., Vol. 16, No. 6, pp. 1141–1147, 2015.

    Article  Google Scholar 

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Correspondence to Keun Park.

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Bae, H., Lee, HJ. & Park, K. Effect of vibration transmission direction in ultrasonic thermoforming on the formability of micro-corrugations. Int. J. Precis. Eng. Manuf. 18, 697–703 (2017). https://doi.org/10.1007/s12541-017-0083-7

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  • DOI: https://doi.org/10.1007/s12541-017-0083-7

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