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Case Study:Importance of Importance of

Fiber Orientation

James Kosloski –CAE Associates

Accurate FEA of Engineering Plastics SeminarO t b 14 2014

© 2014 CAE Associates

October 14, 2014

Case Study – Fiber Orientations

When injection molding glass filled material the fiber orientation will be a When injection molding glass filled material, the fiber orientation will be a function of the molding process.

An injection molding code must be used to calculate the local fiber orientation.

The location of the mold gate will also effect the overall fiber orientation The location of the mold gate will also effect the overall fiber orientation.

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Problem description: Plastic lever Problem description: Plastic lever— Material: Grivory GV4H – 40% Glass Reinforced Polymer— 20 psi pressure load applied.

Find deflections and stresses— Find deflections and stresses

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From Grivory Data Sheet: From Grivory Data Sheet:

— Modulus: 7200 MpaP i ’ R ti 0 37— Poisson’s Ratio: 0.37

— Run analysis as isotropic

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Peak Deformation: 0 038” Peak Deformation: 0.038

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Peak stress: 3784 psi Peak stress: 3784 psi

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However glass filled material is orthotropic to get the However, glass filled material is orthotropic, to get the correct material and orientation a Moldflow analysis was performed on this part courtesy of Joe McFadden at McFadden CAE ServicesMcFadden at McFadden CAE Services

Several tools exist to transfer data between Moldflowand ANSYSand ANSYS.

— We used: Autodesk Moldflow Structural Alliance— Export mesh from ANSYS as STL file.

Perform injection analysis in Moldflow— Perform injection analysis in Moldflow— Analyze in ANSYS with material and fiber direction from

Moldflow Other molding codes can be used as well but Other molding codes can be used as well, but

Moldflow is an industry standard.

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Moldflow Simulation (Courtesy of Joe McFadden) Moldflow Simulation (Courtesy of Joe McFadden).

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Fiber orientation from Moldflow Analysis: Fiber orientation from Moldflow Analysis:

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Deformation based on material orientation imported from Moldflow Deformation based on material orientation imported from Moldflow.

Deformation much lower than isotropic results (0.0267in vs. 0.038)

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Stress in part based on fiber orientation imported from Moldflow Stress in part based on fiber orientation imported from Moldflow.

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Stress is slightly lower (3748 psi vs. 3784 psi)


We will investigate the effect of using a different gate location in the We will investigate the effect of using a different gate location in the molding analysis.

— Analysis courtesy of Joe McFadden.

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New fiber orientations New fiber orientations

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Deformation based on new material orientation imported from Moldflow Deformation based on new material orientation imported from Moldflow.

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Peak deflection 0.0287” increased from end gate analysis (0.0267”)


Stress in part based on fiber orientation imported from Moldflow Stress in part based on fiber orientation imported from Moldflow.

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Peak stress (3774 psi) slightly higher than previous analysis (3748 psi)


These analyses show the importance of accounting for fiber orientations These analyses show the importance of accounting for fiber orientations and orthotropic properties when analyzing glass filled material.

Total deformation Total deformation

Isotropic material Correctly oriented material properties from Moldflow

This is accomplished by using a injection molding analysis and transferingh i l i i d b k i ANSYS

properties from Moldflow

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the material orientation data back into ANSYS.