Researchers butter up the old ‘scratch test’ to make it tough

It might not seem like scraping the top of a cold stick of butter with a knife could be a scientific test, but engineers at MIT say the process is very similar to the “scratch test,” which is perhaps the oldest known way to assess a material’s hardness and strength — or, in scientific language, its resistance to deformation.

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Researchers butter up the old ‘scratch test’ to make it tough