Composites
Building the future with lighter, tougher and more durable composite materials
To achieve the best performance and desired properties in composite materials, the matrix and reinforcing phase are processed to produce extremely complex three-dimensional architectures. Due to this complexity and structural anisotropy, thorough microstructural characterization is crucial, utilizing advanced microscopy techniques.
Investigate composite microstructure for deepest insights
Correlate the microstructure of composite materials at different length scales and use various modalities that will help you in gaining deep materials science insights. While light and electron microscopy techniques permit rapid surface characterization, X-ray microscopy enables full three-dimensional characterization non-destructively, also allowing you to conduct in situ mechanical testing to observe fracture behavior in composite materials.
- Processing: Study the methods and processes used to produce novel fiber composite materials with X-ray Microscopes (XRM) or Scanning Electron Microscopes (SEM).
- Structure: Observe and quantify the produced microstructures in situ non-destructively with XRM, or investigate structure-property relationships with multi-modal microscopy techniques, from Light Microscopy and X-ray Microscopy to taking advantage of Focused Ion Beam Scanning Electron Microscopes (FIB-SEM), combined with correlative software.
- Properties and Performance: Investigate or predict how a composite material, like a woven ceramic matrix composite, will perform in real-world conditions by conducting multi-scale in situ imaging with XRM.
Study The Influence of Processing on Composite Properties
With Light Microscopes, Scanning Electron Microscopes or X-ray Microscopes
To characterize your composite material comprehensively, you will need to perform in situ experiments and investigate details at high magnifications. Benefit from imaging a sample before and after the application of tension or shear using X-ray microscopy and add high resolution imaging in an SEM to complement your analysis.
- Conduct non-destructive, high resolution 3D microstructural analysis of large samples by X- ray microscopy.
- Preserve the sample for additional methods such as dynamic mechanical analysis and mechanical shear tests.
- Use scanning electron microscopy additionally to apply low vacuum, using specific detectors to achieve highly resolved, artifact-free imaging.
- Characterize large surfaces to determine void fractions, fiber orientation and matrix integrity using light microscopes (LM).

Carbon fiber-reinforced composite sample imaged using three different modes – Brightfield, Darkfield and DIC (Differential Interference Contrast) on a ZEISS Axio Imager LM. The three modes provide different contrast revealing details of fibers oriented along different directions. The darkfield contrast provides details related to the matrix.

Carbon fiber composite cross-section taken at 5x magnification ZEISS Axio Imager. The contrast provided by light microscopy enables rapid segmentation and quantification of the void fraction in composite specimens over large areas. Furthermore, high magnification and a combination of filters (fluorescence filter) deliver rapid results on individual fiber placement, spacing and other characteristics over a targeted site of interest that are important to the characterization at the smaller length scales. ZEISS Axio Imager 2, ZEISS Axio Lab.A1, ZEISS Axioscope, ZEISS Axio Zoom.V16.
Observe and Quantify the Structure of Fiber Composites
With Light Microscopes, X-ray Microscopes, FIB-SEM and Software Solutions
Creating structural materials requires you to understand damage initiation and failure mechanisms in structural components. Failures often nucleate inside the bulk, are unobservable until fracture is reached, occur on the microscopic scale, and can exhibit complex 3D characteristics.Mitigate these challenges in characterization and move towards microscopy as a complementary technique to bulk mechanical testing.
- Start the workflow with a light microscope to observe small defects early.
- Employ 3D X-ray microscopy as a second step to examine internal structural damage across multiple length scales,
- Finally, capture characteristic features at the finest length scale using a focused ion beam scanning electron microscope (FIB-SEM).
- With the aid of correlative software, retain the context of all data: FIB-SEM, optical and X-ray techniques.

Multi-scale model of a carbon fiber composite material acquired with correlative microscopy techniques.

Post-tear/delamination observation of a woven carbon fiber composite sample using darkfield mode on a ZEISS Axio-Imager light microscope. The darkfield mode delivers high contrast and enables viewing the half section of the delaminated composite ply, providing unique insights on the distribution of the epoxy within the sample. Using the extended focus function over 40 Z-slices and a large mosaic area, information on the weave quality and the epoxy distrbution can be readily obtained over a wide region of the sample. Sample courtesy of University of Wichita.
Investigate the Properties and Performance of Fiber Composites
With X-ray Microscopes
Find out how materials researchers all over the world are working every day to improve our understanding of fiber composite materials. In this area, there has been a wide range of publications investigating the properties and performance of fiber composite materials with scanning electron microscopy and X-ray microscopy techniques.
- Fracture-resistant silicon carbide ceramic fiber matrix composites
- Non-crimp fabric reinforced polyester composite
- 3D-printed structures
- Hygrothermal aging and structural damage

Nanoscale X-ray tomography of carbon nanotube yarn reveals the orientational domains that are only observed along the axial direction imaged on the ZEISS Xradia Ultra 810 X-ray microscope at 64 nm voxel resolution. Sample courtesy of NASA, US.

Segmented 3D image of the composite, showing E-glass fibers (red), polypropylene fibers (blue), and voids (white spheres), X-ray microscopy.
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