From air filters and water filtration systems to protective clothing and face masks, researchers need to determine the effectiveness of filtration products before releasing them to the public. By analyzing the fibers that make up the filters, they can optimize the performance of a wide range of filtration systems.
In the past, quality control specialists have turned to optical microscopy or atomic force microscopy (AFM) for fiber structural analysis. Yet optical microscopy provides low resolution and requires researchers to manually measure images, while AFM can be slow and uses specialized equipment.
The Phenom Desktop SEM provides superior resolution and depth of field compared to an optical microscope.
By contrast, the Thermo Scientific Phenom Desktop Scanning Electron Microscope (SEM) makes it possible to study fiber properties at the nanometer scale, providing the spatial resolution and depth of field quality control specialists need to quickly evaluate the effectiveness of filtration products. Used in combination with fiber analysis software, it automatically measures the fibers in every image to generate fast and accurate calculations.
With the Phenom Desktop SEM, manufacturers can extend fiber structural analysis to a broader range of users and dramatically increase the speed of their analyses. For example, acquiring and analyzing a dataset of 100 SEM images with 100 measurements per image takes just 10 minutes with the Phenom—versus hours using an optical microscope.
Users can view fiber diameters, orientation, and interconnectivity at high resolution while quickly making the adjustments needed to ensure these products are effective. For example, smaller fiber pore sizes ensure filtration products capture the required particles. Larger pore sizes improve the breathability of filtration products such as face masks and protective clothing.
The Phenom Desktop SEM automatically collects images, producing high-resolution maps that make it fast and efficient to inspect all regions of a filter sample. Used in conjunction with FiberMetric analysis software, it automatically measures the fibers in every image to generate fast and accurate results.
The Phenom Desktop SEM is simpler to use, and cheaper to own and maintain, than traditional floor model systems. It offers several advantages over other desktop SEMs on the market including:
- Sharp, faster fiber imaging: Most Phenom desktop models come with a Cerium hexaboride (CeB6) electron source, which provides high sample signal even when operating in low-vacuum, charge-reduction modes commonly used with fiber imaging. Compared to a Tungsten source, the CeB6 is approximately 10 times brighter, leading to faster and sharper fiber images.
- A robust, easy-to-use electron source: A new CeB6 source has an expected lifetime of at least 1,500 hours, compared to just 50-150 hours for the typical Tungsten. Unlike a Tungsten source, which can fail suddenly and potentially contaminate the column, a CeB6 source slowly degrades over time allowing users to predict its failure and replace it between operating sessions. Only minimal adjustments are required with CeB6 sources, making it easy to obtain consistent filter sample images.
- Minimized shadows along fiber edges: All Phenom models come with an annular back-scatter detector (BSD) positioned directly over the sample surface, minimizing the image shadows along fiber edges. Well-defined fiber edges in the SEM image are a critical feature for accurate fiber diameter measurements, especially when using automated image analysis programs.
- Rapid sample loading: The Phenom includes an efficient and unique sample loading concept that allows for the rapid loading and unloading of sample holders. This loading design allows for efficient structural analysis and fast feedback during fiber production.
- Automated software specifically designed for fiber analysis: The Phenom Desktop SEM integrates with FiberMetric, a purpose-built image analysis program for quantifying fiber diameters, orientations and filter porosity. Designed to accommodate fast workflows, FiberMetric automatically scans each SEM image to provide accurate fiber measurements, generating hundreds of calculations in seconds. The software can quickly analyze images obtained across the entire filter sample or from random areas and provide statistically significant data.
The Phenom Desktop SEM enables automatic, instantaneous fiber property measurements that dramatically decrease the time-to-data for busy industrial labs. It also extends these analyses to workers with limited microscopy training, providing manufacturers with a swift and accurate tool for optimizing the performance of their filtration products.
To learn more about Phenom FiberMetric software, please see our webpage.
Willem van Zyl is an application engineer at Thermo Fisher Scientific.