Microsystem Technologies

, Volume 21, Issue 8, pp 1677–1690

Characterisation of demoulding parameters in micro-injection moulding

  • C. A. Griffiths
  • G. Tosello
  • S. S. Dimov
  • S. G. Scholz
  • A. Rees
  • B. Whiteside
Technical Paper

Abstract

Condition monitoring of micro injection moulding is an effective way of understanding the processing effects of variable parameter settings. This paper reports an experimental study that investigates the characteristics of the demoulding behaviour in micro injection moulding (µ-IM) with a focus on the process factors that affect parts’ quality. Using a Cyclic Olefin Copolyme (COC) microfluidics demonstrator, the demoulding performance was studied as a function of four process parameters (melt temperature, mould temperature, holding pressure and injection speed), employing the design of experiment approach. The results provide empirical evidences on the effect that processing parameters have on demoulding conditions in µ-IM, and identifies combinations of parameters that can be used to achieve the optimal processing conditions in regards to demoulding behaviour of micro parts. It was concluded that there was a direct correlation between the applied pressure during part filling, holding phases and the demoulding characteristic factors of the µ-IM cycle such as ejection force, integral and time.

Abbreviations

ANOVA

Analysis of variance

ABS

Acrylonitrile butadiene styrene

COC

Cyclic olefin copolymer

d

Measuring pin diameter

DOE

Design of experiments

IM

Injection moulding

OA

Orthogonal array

PC

Polycarbonate

PVT

Pressure volume temperature

List of symbols

Fe

Demoulding force

\( {\text{F}}_{{\rm max} }^{\text{e}} \)

Maximum demoulding force

\( {\text{F}}_{\text{work}}^{\text{e}} \)

Demoulding force work

\( {\text{F}}_{\text{rate}}^{\text{e}} \)

Demoulding force rate

Ph

Holding pressure

S/N

Signal to noise ratio

SVR

Surface to volume ratio

t

Time

Tb

Melt/barrel temperature

th

Holding pressure time

Tm

Mould/tool temperature

Tg

Glass transition temperature

Vi

Injection speed

Δt

Time step of data acquisition system

δ

Relative effect

σ

Standard deviation

μ-IM

Micro-injection moulding

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Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  • C. A. Griffiths
    • 1
  • G. Tosello
    • 2
  • S. S. Dimov
    • 3
  • S. G. Scholz
    • 4
  • A. Rees
    • 5
  • B. Whiteside
    • 6
  1. 1.School of Mechanical, Aerospace and Civil EngineeringThe University of ManchesterManchesterUK
  2. 2.Department of Mechanical EngineeringTechnical University of DenmarkKongens LyngbyDenmark
  3. 3.School of Mechanical EngineeringBirmingham UniversityBirminghamUK
  4. 4.Institute for Applied Computer ScienceKarlsruhe Institute of TechnologyKarlsruheGermany
  5. 5.College of EngineeringSwansea UniversitySwanseaUK
  6. 6.Centre for Polymer Micro and Nano TechnologyUniversity of BradfordBradfordUK

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