Material Characterization and Constitutive Modeling of PMMA for the Numerical Simulation of Vacuum Forming Process

Abstract:

In this study, the thermomechanical behavior of PMMA(poly-methyl methacrylate) during high-temperature vacuum forming was analyzed through both experimental and computational approaches. The material behavior of PMMA was modeled as a temperature and strain-rate dependent viscoplastic response, coupled with time-dependent creep deformation. The creep behavior was represented by the Norton–Bailey power law (Eq. 1), while the constitutive model for the strain rate and temperature-dependent stress-strain behavior was implemented in ABAQUS via a user subroutine (UHARD). The forming process was simulated by using ABAQUS/Standard VISCO solver, incorporating vacuum pressure loading and clamping conditions. The numerical framework enables effective analysis of deformation behavior under thermomechanical forming conditions and provides a basis for process-oriented modeling of PMMA vacuum forming.

• Periodical: Defect and Diffusion Forum (Volume 451)
• Pages: 95-101
• DOI: https://doi.org/10.4028/p-Is2sE9
• Online since: April 2026
• Authors: Hyunsung Choi*, Minjae Baek, Yong Nam Kwon, Ducksung Kim, Daeho Jeong, Yoo In Jeong
• Keywords: Creep Model, Polymethyl Methacrylate (PMMA), Vacuum Forming, Viscoplastic Model

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