Hardness evaluates a material's ability to resist mechanical wear and abrasion. Alumina ceramics surpass steel and tungsten carbide tools in hardness. About the Rockwell hardness scale, alumina ceramics vary from HRA80-ninety, placing them just under diamonds and higher than stainless steel. Iolite ceramics are perfect square mirror elements for lithography https://johnr775csg2.shivawiki.com/user