| abstract |
A ceramic composition which is mainly composed of alumina (Al 2 O 3 ), tungsten carbide (WC) and zirconia (ZrO 2 ), and wherein zirconium (Zr) is distributed in a first grain boundary, which is the interface where an alumina (Al 2 O 3 ) crystal grain and a tungsten carbide (WC) crystal grain are adjacent to each other, and in a second grain boundary, which is the interface where two alumina (Al 2 O 3 ) crystal grains are adjacent to each other. |