| abstract |
[PROBLEMS] To provide a high-strength alumina-based sintered body which has improved bending strength and hardness compared to conventional alumina-based sintered bodies, slightly reduced fracture toughness, and has excellent free-cutting properties. provide. The sintered body contains 50 to 97% by weight of alumina and 3 to 50% by weight of aluminum and yttrium garnet, and has an average crystal grain size of 2 to 2 in a sintered body. 10 μm and the average crystal grain size of aluminum yttrium garnet is 1.5 to 5 μm, Further, the ratio of the average crystal particle diameter of alumina to the average crystal particle diameter of aluminum, yttrium, and garnet is larger than 1 and smaller than 7, thereby forming a high-strength alumina-based sintered body having excellent free-cutting properties. |