Integrated Numerical Simulation for SMC in Compression Molding Process

Compression molding is an effective high volume and net-shape fabrication method for aspherical lenses and precision glass optical components in general. Geometrical deviation (or curve change as often referred to in industry) incurred during heating, molding, and cooling processes is a critically important manufacturing quality parameter. In the compression glass molding process, there are many factors that could lead to curve change in final products, such as thermal expansion, stress and structural relaxation, and inhomogeneous temperature distribution inside the molding machine. In this research, an integrated numerical simulation scheme was developed to predict curve change in molded glass aspherical lenses. The geometrical deviation in the final lens shape was analyzed using both an experimental approach and a numerical simulation with a finite element method program. Specifically, numerical simulation was compared with experimental results to validate the proposed manufacturing approach. The measurements showed that the difference between numerical simulation and experimental results was less than 2 μm. Based on the comparison, the mold curve was revised using numerical simulation in order to produce more accurate lens shapes. The glass lenses molded using the compensated molds showed a much better agreement with the design value than the lenses molded without compensation. It has been demonstrated in this research that numerical simulation can be used to predict the final geometrical shape of compression molded precision glass components. This research provided an opportunity for optical manufacturers to achieve a lower production cost and a shorter cycle time.

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Numerical simulation for predicting sink marks on injection molding and injection compression molding process

10.1063/1.5142929 ◽

2020 ◽

Author(s):

Yen-Chih Chen ◽

Chih-Chung Hsu ◽

Chia-Hsiang Hsu

Keyword(s):

Numerical Simulation ◽

Injection Molding ◽

Compression Molding ◽

Molding Process ◽

Sink Marks ◽

Injection Compression Molding

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Numerical Simulation and Process Optimization of a 3D Thin-Walled Polymeric Part Using Injection Compression Molding

International Polymer Processing ◽

10.1515/ipp-2020-4075 ◽

2021 ◽

Vol 36 (4) ◽

pp. 459-467

Author(s):

D. Sönmez ◽

A. A. Eker

Keyword(s):

Numerical Simulation ◽

Injection Molding ◽

Process Parameters ◽

Compression Molding ◽

Injection Molding Process ◽

Mold Surface ◽

Clamping Force ◽

Molding Process ◽

Thin Walled ◽

Injection Compression Molding

Abstract Injection compression molding (ICM) is a hybrid injection molding process for manufacturing polymer products with high precision and surface accuracy. In this study, a 3D flow simulation was employed for ICM and injection molding (IM) processes. Initially, the process parameters of IM and ICM were discussed based on the numerical simulations. The IM and ICM processes were compared via numerical simulation by using CAE tools of Moldflow software. The effect of process parameters of mold surface temperature, melting temperature, compression force and injection time on clamping force and pressure at the injection location of molded 3D BJ998MO Polypropylene (MFI 100) part was investigated by Taguchi analysis. In conclusion, it was found that the ICM has a relatively lower filling pressure than ICM, which results in reduced clamping force for producing a 3D thin-walled polymeric part.

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A Study of Processing Conditions on the Properties of Diffraction Optical Elements by Injection/Compression Molding Process

International Polymer Processing ◽

10.3139/217.1733 ◽

2003 ◽

Vol 18 (2) ◽

pp. 194-198 ◽

Cited By ~ 5

Author(s):

S. C. Tseng ◽

C. L. Liao

Keyword(s):

Compression Molding ◽

Processing Conditions ◽

Molding Process ◽

Optical Elements ◽

Injection Compression Molding ◽

Diffraction Optical Elements

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Innovation in Aircraft Cabin Interior Panels Part I: Technical Assessment on Replacing the Honeycomb with Structural Foams and Evaluation of Optimal Curing of Prepreg Fiberglass

Polymers ◽

10.3390/polym13193207 ◽

2021 ◽

Vol 13 (19) ◽

pp. 3207 ◽

Cited By ~ 1

Author(s):

Edgar Adrián Franco-Urquiza ◽

Annika Dollinger ◽

Mauricio Torres-Arellano ◽

Saúl Piedra ◽

Perla Itzel Alcántara Llanas ◽

...

Keyword(s):

Weight Ratio ◽

Viscoelastic Behavior ◽

Compression Molding ◽

Polyurethane Foams ◽

Future Research ◽

Honeycomb Core ◽

Molding Process ◽

Aircraft Cabin ◽

Structural Applications ◽

Cabin Interior

Sandwich composites are widely used in the manufacture of aircraft cabin interior panels for commercial aircraft, mainly due to the light weight of the composites and their high strength-to-weight ratio. Panels are used for floors, ceilings, kitchen walls, cabinets, seats, and cabin dividers. The honeycomb core of the panels is a very light structure that provides high rigidity, which is considerably increased with fiberglass face sheets. The panels are manufactured using the compression molding process, where the honeycomb core is crushed up to the desired thickness. The crushed core breaks fiberglass face sheets and causes other damage, so the panel must be reworked. Some damage is associated with excessive build-up of resin in localized areas, incomplete curing of the pre-impregnated fiberglass during the manufacturing process, and excessive temperature or residence time during the compression molding. This work evaluates the feasibility of using rigid polyurethane foams as a substitute for the honeycomb core. The thermal and viscoelastic behavior of the cured prepreg fiberglass under different manufacturing conditions is studied. The first part of this work presents the influence of the manufacturing parameters and the feasibility of using rigid foams in manufacturing flat panels oriented to non-structural applications. The conclusion of the article describes the focus of future research.

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BVID analysis of non-crimp fabric cross-ply laminate manufactured through wet compression molding process

AIAA Scitech 2020 Forum ◽

10.2514/6.2020-0727 ◽

2020 ◽

Author(s):

Sooyoung Lee ◽

Chaeyoung Hong ◽

Taeseong Choi ◽

Hye-gyu Kim ◽

Wooseok Ji

Keyword(s):

Compression Molding ◽

Molding Process ◽

Wet Compression

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Study on Processes and Properties of Continuous Woven Roving Reinforced Polyurethane Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.306-307.879 ◽

2011 ◽

Vol 306-307 ◽

pp. 879-883 ◽

Cited By ~ 1

Author(s):

Xiao Li Dai ◽

Xiang Wang ◽

Jun Wang

Keyword(s):

Mass Fraction ◽

Interfacial Adhesion ◽

Bending Strength ◽

Compression Molding ◽

Micro Structure ◽

Molding Process ◽

Elongation At Break ◽

Vacuum Infusion ◽

Polyurethane Composites ◽

Sem Morphology

E-glass fiber woven roving reinforced polyurethane composites were manufactured by three different processes: hand lay-up, compression molding and vacuum infusion to assess the feasibility of all the processes. The results showed that all composites led to significant improvements in both flexural and tensile properties except elongation at break in comparison with the neat PU. Among the three processes, the best bending strength was exhibited by the hand lay-up process. This is attributed to higher PU mass fraction leads to a better fiber–matrix interfacial adhesion. Mechanical properties of the composite molded by vacuum infusion were superior to that produced by compression molding process. The SEM morphology revealed that vacuum infusion composite had more homogeneous micro- structure.

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