It was a graphite-based material with an adhesive backing and I didn't insert it perfectly the first time. When I tried to remove it, the trouble began. The adhesive on the material stuck right onto my aluminum testing block and I could not get it off.
My first attempt to remove the material was with mechanical scrubbing. This took off chunks of the top layer of material, but left much of the material with the adhesive behind. After doing this, my test vehicle and the table I was working on were covered in graphite scrapings.
The second attempt began with a solvent soak in addition to scrubbing. IPA didn't touch it so I tried to turn up the power with acetone to no assistance. My final resort was for methyl ethyl ketone which I had to borrow from another department. This worked, but wasn't a material I typically keep in the lab and wasn't happy to have spattering around.
Out of this experience I learned how blessed I am to be the manufacturer of clean, solid metal thermal interface materials so that my testing doesn't have to revolve around these messy materials often.
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