Root Cause Analysis of Failure in Carbon Fiber Reinforced Plastics (CFRP) and Glass Fiber Reinforced Plastics (GFRP)

JFE-TEC is ready to study the root cause of failure in carbon fiber reinforced plastics (CFRP) and glass fiber reinforced plastics (GFRP) used in a wide field.

Failure Analysis of the Fiber Reinforced Composite Materials - Its Importance and the Outline

Fiber reinforced composite materials are used in a wide field because of its strength and light weight. Carbon fiber reinforced plastics (CFRP), one of the fiber reinforced composites is injection-molded to the parts, which use the fibers and the matrix resin at their interfaces potentially causing various problems. The root cause analysis of failure of the CFRP products becomes more important in recent years.

JFE-TEC has expertise and experience with the chemical analysis and the root cause analysis of a wide variety of metals, resins, and the resin composites and the fiber reinforced composite material is one of them.

Analysis Subjects

• • Analysis of matrix resins by FT-IR spectroscopy, differential scanning calorimetry (DSC), pyrolysis gas chromatography mass spectrometry (Py-GC/MS)
  • Analysis of the structure of fiber- matrix resin by optical emission analysis with a charge-coupled detector (CCD) camera and scanning electron microscopy (SEM)
  • Morphological analysis of fibers by optical emission analysis with CCD camera and SEM
• • Evaluation of mechanical properties in products (material testing)
  • Morphological analysis of fracture sections in the products by optical emission analysis with CCD camera and SEM
  • Non-destructive testing of the product by ultrasonic infrared thermography

Example of failure analysis

• A possible root cause of fracture in the fiber reinforced composite materials includes:

  • Uneven distribution of fibers in the matrix resin
  • Formation of voids in the matrix resin
  • Contamination with foreign particles
  • Fiber meandering, and
  • Delamination of fiber layers

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In particular delamination of the fiber layers is a critical issue. The fiber reinforced composite is strong against the external force in the fiber direction but weak in other direction of force, potentially resulting in very poor compression strength when delamination occurs between the fiber layers in the laminates.