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Scientists have discovered
razor blades become blunt after repeated
. They did research on why blades lose their
. Razors are 50
harder than hair. Even though hair is 50 times softer than the
of a razor, the hair damages the
of the blade. Razor blades are made from
steel and coated with tough materials like carbon. The scientists said
time a blade cuts a hair, the hair causes tiny
of damage. A blade can cut thousands of hairs. This means the life of a razor blade is limited. It needs to be replaced
.
