Material Modeling of PMMA Film for Hot Embossing Process

Area of Science:

• Materials Science and Engineering
• Computational Mechanics
• Polymer Processing

Background:

• Hot embossing is crucial for micro/nano pattern fabrication on polymer films.
• Analyzing the complex hot embossing process with poly methyl methacrylate (PMMA) requires extensive experimentation.
• Process variations significantly impact the quality of embossed patterns, necessitating efficient analysis methods.

Purpose of the Study:

• To develop and validate a computational analysis method for optimizing the hot embossing process of PMMA films.
• To reduce the time and cost associated with traditional experimental approaches.
• To precisely analyze the film deformation during hot embossing.

Main Methods:

• Utilized the finite element method (FEM) coupled with the arbitrary Lagrangian-Eulerian (ALE) re-mesh technique.
• Developed a constitutive model incorporating strain, strain rate, and temperature-dependent stress and softening.
• Implemented the constitutive model via a user-subroutine for detailed embossing analysis.

Main Results:

• The developed constitutive model accurately captured the work hardening, strain softening, and temperature-softening behavior of PMMA.
• The FEM-ALE approach provided a precise simulation of the film's behavior during the hot embossing process.
• The computational method demonstrated potential for rapid identification of optimal process conditions.

Conclusions:

• Computational analysis using FEM and a validated constitutive model offers an efficient alternative to experimental methods for hot embossing optimization.
• The proposed approach enables accurate prediction of material behavior and pattern formation.
• This method facilitates faster development cycles and cost reduction in micro/nano fabrication using hot embossing.