Definition: Overhardness, also known as "overharding" or "overharding effect," is a phenomenon observed in certain types of crystals such as diamond and silicon carbide. It refers to the increase in hardness of materials due to an increase in the volume fraction of ungrit material (the "non-grit" part) compared to the original material. In other words, overhardness occurs when the volume fraction of non-grit material increases relative to the original material. This can
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