X-ray Computed Tomography for Materials and Life Science

Webinar summary

X-ray CT is a powerful non-destructive method for inspecting medical devices and healthcare products because it reveals internal structures without cutting, sectioning, or otherwise damaging the part. That makes it useful for determining whether a device has been built correctly, whether internal components match the intended design, and whether hidden damage, voids, leaks, or assembly defects are present. It can support work across the entire product lifecycle, including early material selection, prototype development, validation, quality control, and failure analysis. In many cases, conventional 2D X-ray remains the faster option for routine screening, but CT becomes especially valuable when a full three-dimensional understanding is needed, particularly for root-cause investigations and situations where internal geometry matters.

Medical devices span an enormous range of designs and materials, so CT strategy has to be tailored to the sample. Four factors are especially important: what the part is made of, how dense it is, how large it is, and how small the features of interest are. Low-density materials such as plastics, plant-based media, and porous fiber structures require different scan conditions than dense components such as metal implants, pacemakers, or spring-loaded assemblies. Multi-material devices can be particularly challenging because they may combine plastic housings, metal parts, glass, adhesives, and air gaps within a single product. Each of these materials interacts differently with X-rays, so image quality depends heavily on setting the right scan conditions.

Because CT is an absorption imaging method, contrast comes from the amount of X-ray energy absorbed as the beam passes through the sample. Thicker and denser materials absorb more strongly and appear brighter in reconstructed images, while air and low-density materials appear darker. This makes it possible to distinguish components and voids, but it also introduces complications. Highly absorbing materials, especially metals, can create artifacts, which appear as grayscale features that do not correspond to the actual physical structure. These artifacts can obscure nearby details and make interpretation harder. They can often be reduced by adjusting X-ray energy, changing voltage, using metal filters such as aluminum or copper, and carefully choosing sample orientation so the beam does not pass through unnecessarily thick regions.

One important application is failure analysis. In a plastic component where a tube was heat-welded to a molded body, CT was used after a leak test failure to determine how far the defect extended and which internal voids were connected to outside air. Cross-sectional views and segmentation tools made it possible to separate solid material from empty space and identify the leak path. That kind of analysis is difficult or impossible to perform as effectively with destructive sectioning because slicing the part can alter the evidence or miss the actual pathway. By revealing the true internal geometry, CT gives engineers information they can use to modify joining processes and improve manufacturing consistency.

CT is also well suited to highly compact consumer-style healthcare devices in which multiple components are crowded into very small volumes. In miniature wearable devices, for example, CT can reveal how batteries, substrates, seals, and electronic components are arranged, and it can expose defects such as internal gaps, layer separation, wrinkling, or poor seating of parts that are not visible from the outside. Comparing different internal layouts can show how design choices affect available battery volume, structural support, and assembly quality. This is especially useful as devices continue to shrink and manufacturers need to pack more functionality into less space without sacrificing reliability.

Another major use is dimensional analysis. CT data can be compared directly against CAD geometry to generate color maps showing where a manufactured part deviates from the intended design. This is particularly valuable for injection-molded components, where warpage, shrinkage, flash, or local dimensional variation may affect fit and performance. Because the full internal and external geometry is captured in three dimensions, CT can evaluate features that are difficult to reach with tactile metrology and can do so without cutting the part apart. The method therefore supports both design verification and process improvement.

CT can also characterize soft, porous, and fibrous materials used in products such as bandages, filters, and dialysis media. By segmenting fibers and binders in the reconstructed volume, software can generate a digital representation of the internal structure and use it to simulate behavior such as fluid flow, pressure drop, and particle capture. This extends CT beyond simple inspection into structure-performance analysis, where internal architecture can be linked to how the product functions in practice. That is especially valuable for materials in which performance depends on pore network connectivity, fiber distribution, or the spatial relationship between multiple phases.

Resolution is one of the most important practical constraints. A rough rule is that voxel size scales with the field of view, so scanning a larger object or a larger region generally reduces the ability to resolve fine detail. To see smaller features, the part must be moved closer to the X-ray source to increase magnification, which narrows the field of view but improves spatial resolution. That creates a constant tradeoff between seeing the whole device and seeing tiny internal features clearly. In practice, some tasks require a broad overview scan, while others require zoomed-in, high-resolution imaging of a specific area. For some products, a multiscale approach is the most effective way to connect whole-part context with microscopic detail.

Sample orientation matters as well because absorption increases sharply with thickness. A poorly oriented sample may force the beam through too much material, increasing noise and artifacts. Reorienting the part is often one of the first and most effective ways to improve image quality, especially for complex shapes or parts containing dense inserts. Identifying thin polymer layers near dense materials is particularly challenging because the contrast between the layers may be weak while the dense material dominates the image. In those cases, careful optimization of energy and filtering is essential.

The most suitable instrument depends on the energy and resolution required. Medium-scale systems are useful for many electronic or mixed-material parts, while higher-resolution systems are needed for sub-micron detail, and higher-voltage systems are better suited for dense implants or other strongly absorbing samples. Access to CT generally follows three models. Some users begin with feasibility work in university core facilities or vendor laboratories. Others use contract research organizations or purchase an initial versatile system while they develop expertise. Organizations with higher sample volume or stricter turnaround, confidentiality, or intellectual-property requirements often bring CT fully in-house. In-house capability provides greater control and faster iteration, but it also requires trained staff and internal method development.

Cost scales with system capability. Benchtop systems typically fall in the low hundreds of thousands of dollars, while high-resolution or high-voltage systems can reach into the millions depending on their features. Automation can extend throughput through approaches such as longer travel ranges or sample changers for handling multiple parts. General scan protocols can be developed based on part size and material composition, but successful use still depends on matching the method to the specific device and question being asked. Taken together, the information shows CT as a flexible inspection and analysis tool that helps manufacturers understand internal structure, verify quality, solve failures, and relate design choices to performance without destroying the product.