While characterizing the epoxy samples mentioned earlier, we encountered a challenge when increasing the ratio of plasticizer—the DMA (dynamic mechanical analyzer) machine couldn’t break the samples. Unfortunately, our current DMA had a maximum force limit of 400 newtons. Fortunately, we had access to another DMA, albeit set up with clamps for viscoelastic materials and lacking 3-point-bending tools.

To overcome this, I designed and 3D printed adapters that could integrate with the alternate DMA apparatus. These adapters included a top piece with embedded neodymium magnets, ensuring secure attachment of the tooling without risk of dislodging. Thanks to these custom adapters, we managed to successfully conduct our research within the constraints of our available time.

 

In 2018, I had the privilege of spending the summer at Northwestern University’s MRSEC (Materials Research Science and Engineering Center). During this time, my focus was on characterizing fracture toughness in epoxy polymers at cryogenic temperatures, specifically for aerospace applications, involving a major space launch service provider.

One significant challenge I faced was using a dynamic mechanical analyzer to determine the maximum stress epoxy samples could endure before failure. Unfortunately, the samples frequently failed during the cooling phase when gaseous LN2 was introduced into the sample chamber. This was exacerbated by the thinness of the samples, the rapid gas influx, and the shrinkage of the 3-point bending apparatus, which continually compromised the experiments by causing sample instability.

Fortunately, Northwestern’s engineering center offered access to Stratasys FDM 3D printers. After careful consideration, I devised a solution—a U-shaped saddle that could be integrated into the 3-point bending tools to securely hold the samples upright without affecting the experimental integrity. Although seemingly simple, this innovation was a critical and non-trivial resolution to an ongoing experimental challenge.