Microsystem Technologies

, Volume 22, Issue 4, pp 687–698 | Cite as

Replication quality of micro structures in injection moulded thin wall parts using rapid tooling moulds

Technical Paper

Abstract

Injection moulding of micro structured polymer parts is often limited due to the replication quality of the structured surfaces. To enhance the replication quality process parameters, e.g., pressure, temperature or injection velocity, are adapted. Here, the mould temperature is the most important factor. This paper investigates the influence of the mould temperature on the replication of micro structured surfaces using amorphous and semi-crystalline polymers. Using rapid tooling moulds and a dynamic tempering system allows mould temperatures about the solidification temperatures during injection and a sufficient cooling for save ejection of the part. The results reveal that for amorphous polymers the mould temperature should be above the glass transition temperature for high replication quality. For semi-crystalline polymers the high cooling velocity seems to inhibit the crystallization process and this leads to a sufficiently low viscosity to achieve high replication quality.

Notes

Acknowledgments

The authors would like to thank the Bavarian Research Foundation for funding the work. We also extend our gratitude to our industrial partners Werkzeugbau Hofmann GmbH, Oechsler AG, Single Temperiertechnik GmbH, hotec GmbH, Arburg GmbH & Co. KG, Sabic Europe and Bayer MaterialScience AG for providing equipment and material. They further thank Mrs. Pia Trawiel and Mrs. Birgit Kaiser for supporting the measurements.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  • Steve Meister
    • 1
  • Andreas Seefried
    • 1
  • Dietmar Drummer
    • 1
  1. 1.Institute of Polymer TechnologyFriedrich-Alexander-Universität Erlangen-NürnbergErlangen, TennenloheGermany

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