Numerical investigation of wrinkle for multi-point thermoforming of Polymethylmethacrylate sheet

2017 3rd International Conference on Applied Materials and Manufacturing Technology

Peng, Heli^1 ; Liu, Haijian^1 ; Zhang, Xiaolong^1

Shanghai Spaceflight Precision Machinery Institute, Shanghai

201600, China^1

关键词: Effects of thickness;    Forming temperature;    Material parameter;    Multi-points;    Numerical investigations;    Numerical results;    Stress-relaxation curves;    Wrinkle-forming;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/242/1/012028/pdf
DOI  :  10.1088/1757-899X/242/1/012028

来源: IOP

【 摘 要 】

The multi-point thermoforming (MPTF) machine and process of resin sheet were introduced, the glass transition temperature and stress relaxation curves of Polymethylmethacrylate (PMMA) sheet were tested, and the material parameters of PMMA sheet were got. Lots of numerical simulation of wrinkle for spherical part with MPTF of PMMA sheet were put forward, the effects of thickness, radius and forming temperature on the wrinkle were investigated, and the non-wrinkle forming limit diagram are determined. Then, MPTF experiments of spherical part with PMMA sheet was done to verify the numerical results. Consequently, the spherical part has good shape accuracy, which confirms that PMMA sheet formed by MPTF is feasible and the non-wrinkle forming limit diagram obtained by numerical simulation is practicable.