Options
Characterization of microinjection molding process for milligram polymer microparts
Author(s)
Date Issued
2013-08-02
Date Available
2014-09-29T11:11:44Z
Abstract
Injection molding small milligram components requires precise metering and high-speed injection. Industrially, metering can be maintained either by using small injection screws (≤14 mm in diameter) or plungers as small as 3 mm diameter and/or by having very large sprues and runners. Although large sprues and runners increase metering volume, they hide the effect of process parameters on microcomponents. Consequently, knowledge of conventional injection molding is not transferable to microinjection molding, making quality control and optimization difficult. We investigated the filling and postfilling behavior of 25 mm3 microdumbbell specimens with 289 mm3 sprue and runner by in-line process monitoring. Design of Experiments were carried out to characterize the effects of process parameters on cavity filling and postfilling behavior. Process characterization indicated that the machine transition from velocity control to pressure control (V-P transition) was around 10 ms: this was comparable to cavity filling time and had a significant effect on cavity filling behavior. Traditional short shot trials cannot provide the correct shot size for small parts, but introduce the effect of holding pressure into cavity filling. Based on a shot size optimization method using only cavity pressure and screw velocity, we eliminated the effect of holding parameters on cavity filling.
Type of Material
Journal Article
Publisher
Wiley Blackwell (John Wiley & Sons)
Journal
Polymer Engineering & Science
Volume
54
Issue
6
Start Page
1458
End Page
1470
Copyright (Published Version)
2013 Wiley Blackwell (John Wiley & Sons)
Language
English
Status of Item
Peer reviewed
This item is made available under a Creative Commons License
File(s)
Owning collection
Scopus© citations
16
Acquisition Date
Mar 28, 2024
Mar 28, 2024
Views
1507
Acquisition Date
Mar 28, 2024
Mar 28, 2024
Downloads
838
Last Week
1
1
Last Month
11
11
Acquisition Date
Mar 28, 2024
Mar 28, 2024