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The researchers used
to look at how hair damages razor blades. They got a close-up
of what happens when the blade cuts a
. One cause of damage is because a hair can make a
chip on the
of a blade. This chip gets bigger as it cuts more hair. After more shaving, the blade loses its
to cut cleanly. A researcher said he wanted to make
stronger. He said it was interesting that, "if you cut something very
, like human hair, with
very hard, like steel, the hard material would fail." He called this "an important engineering
".
