Related Experiment Video
Updated: Aug 7, 2025
05:32
A Soft Tooling Process Chain for Injection Molding of a 3D Component with Micro Pillars
Published on: August 4, 2018
12.7K
Adhesion-Induced Demolding Forces of Hard Coated Microstructures Measured with a Novel Injection Molding Tool
Maximilian Schoenherr1, Holger Ruehl2, Thomas Guenther2
1Institute of Design and Production in Precision Engineering (IKFF), Faculty 7-Engineering Design, Production Engineering and Automotive Engineering, University of Stuttgart, Pfaffenwaldring 9, 70569 Stuttgart, Germany.
Polymers
|March 11, 2023
Summary
Demolding plastic parts is difficult. A new injection molding tool measures adhesion forces, revealing chromium nitride (CrN) coatings reduce demolding force by 98.5%, significantly improving the process.
Area of Science:
- Materials Science
- Manufacturing Engineering
Background:
- Demolding plastic parts in injection molding presents significant challenges.
- Existing measurement tools often focus on friction or specific geometries, neglecting adhesion forces.
Purpose of the Study:
- To introduce a novel injection molding tool designed to measure adhesion-induced tensile forces.
- To separate adhesion force measurement from the part ejection process.
Main Methods:
- Developed a new injection molding tool utilizing adhesion-induced tensile force measurement.
- Verified functionality by molding PET specimens under varying mold temperatures, insert conditions, and geometries.
- Employed an integrated camera for monitoring the specimen-mold interface.
Main Results:
- The tool accurately measured demolding force with low variance after achieving thermal stability.
- Chromium nitride (CrN) coated mold inserts reduced demolding force by 98.5% compared to uncoated and diamond-like carbon coated inserts.
- Adhesion forces were significantly reduced by CrN coatings.
Conclusions:
- The novel tool effectively measures adhesion forces in injection molding.
- CrN coatings offer a highly efficient solution for reducing demolding forces by minimizing adhesive bond strength.
- This technology can significantly improve plastic part demolding efficiency.
