Where to carry out analysis on carbon/epoxy composites

Parts made of carbon/epoxy composites are subject to high requirements in terms of mechanical performance, service life, adhesion and surface stability. In the event of failure, delamination, impregnation defect, formulation variation, surface contamination, adhesion problem or premature aging, it is necessary to carry out targeted composite analysis. The challenge is to quickly identify the physico-chemical origin of the defect, compare a compliant batch with a non-compliant batch, or document a supplier qualification and quality control process.

composite analysis may aim to identify the polymer matrix, confirm a copolymeric nature, perform a qualitative search for monomers, oligomers, residual solvents and organic additives, as well as determine the mass fraction of mineral fillers. Morphological observation and elemental identification of the fillers also make it possible to better understand the material’s base formulation. To go further in organic investigations, extraction followed by chromatography can be used, in particular to search for plasticizers, antioxidants, UV stabilizers or other semi-volatile and non-volatile compounds. Depending on the need, these studies can be supplemented by dedicated methods such as HPLC MS analysis or HPLC RI analysis.

Characterizing a carbon/epoxy composite often requires a multi-scale approach. SEM-EDX makes it possible to observe morphology, interfaces, cross-section defects and obtain local elemental identification. XPS provides detailed information on the chemical composition of the first surface layers. AFM and the roughness meter document topography and roughness parameters useful for adhesion. In addition, trace metal or elemental contaminant analysis can be integrated when mineral contamination, a foreign particle or a process drift is suspected. To discover other instrumental capabilities, you can consult the Met Analysis Laboratory.

Filab supports manufacturers with material qualification issues, batch comparisons, failure analysis, process validation and conformity control. The advantage for manufacturers and users of carbon/epoxy composites is having a contact who can quickly structure the analytical plan, sample preparation, multi-technique testing and cross-reading of results. This approach is suited to sectors where reliability, traceability and performance requirements are high.

The laboratory supports manufacturers in the characterization of organic matrix composite materials, from surface analysis to cross-section study, additive research, identification of mineral fillers and detection of elemental contaminants. Depending on the objective, the investigations may combine microscopy, elemental analysis, surface chemical analysis and chromatography techniques. This multi-technique approach makes it possible to confirm the nature of a treatment, verify the uniformity and thickness of layers, observe corrosion or coating failure, and interpret composition differences between samples.

When the performance of the composite depends heavily on its surface condition or on an applied treatment, surface chemical analysis makes it possible to confirm the nature of the layers present and detect any deviations. Cross-section analysis are used to verify layer uniformity, continuity, thickness and the absence of delamination. Surface topography can also be studied to characterize the surface condition before bonding, painting or assembly. For these needs, techniques such as XPS, SEM-EDX, AFM or TOF-SIMS are particularly relevant, with the possibility of going further via TOF-SIMS Fiber analysis.

For the organic matrix, pyrolysis coupled with chromatography or post-extraction analysis make it possible to identify the polymer, copolymer, characteristic fragments, residual solvents and additives. The search for volatile, semi-volatile and non-volatile organic impurities helps explain differences in behavior, odor, thermal stability or suitability for assembly. Gas chromatography methods can be used to confirm the presence of targeted compounds or compare several references, notably via the GC Tea Analysis Laboratory.

The laboratory deploys dedicated human and technical resources to develop or adapt an analytical strategy to the matrix under study. Support can cover one-off investigations, comparative studies, method development, analytical validation and assistance with method transfer. This organization makes it possible to respond to urgent requests as well as to more structured projects related to process optimization, supplier qualification or understanding a competitor material.

To start a study, it is recommended to specify the type of composite, the function of the part, the context in which the defect appeared, any treatments or coatings, the number of samples available, and the expected objective: compare, identify, confirm, quantify, or assess. Based on this information, a test program can be built using the most relevant techniques. To move forward efficiently, the surfaces should be analyzed, the matrix characterized, compliant and non-compliant areas compared, contaminants identified, layer thickness verified, and the results interpreted in light of the process and the final use.