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Spotlight: Putting Materials to the Test With Our Advanced Weathering Machine

Not to be confused with the 1990s sci-fi film, NIST’s SPHERE (aka Simulated Photodegradation via High Energy Radiant Exposure) puts materials through the wringer, mimicking days, weeks or years of exposure to the elements.

A high-intensity ultraviolet light source at the center of the machine can generate 60 times the irradiance levels of the Sun. The light shines inside chambers on the periphery of the device where samples are held. There, temperature and humidity can be tightly controlled.

Joannie Chin, now acting director of NIST’s Engineering Laboratory, worked on building SPHERE from the ground up earlier in her career as a polymer scientist, starting in 1996. At the time, she focused on evaluating polymers for use in bridges and buildings, and she needed to know how they would handle weathering over time.

But the uses of Joannie’s patented SPHERE grew beyond construction materials. Our researchers use the machine to break down specimens even today, exploring everything from body armor to solar panels.

NIST’s SPHERE (Simulated Photodegradation via High Energy Radiant Exposure) puts materials through the wringer, mimicking days, weeks or years of exposure to the elements. A high-intensity ultraviolet light source at the center of the machine can generate 60 times the irradiance levels of the Sun. The light shines inside chambers on the periphery of the device where samples are held. There, temperature and humidity can be tightly controlled. Our researchers use the machine to break down specimens to explore everything from body armor to solar panels.

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Released May 18, 2021, Updated June 7, 2021