Abstract: An advanced Al2O3/(W, Ti) C composite ceramic tool material reinforced by rare earth elements is developed, and the toughening and strengthening mechanisms are analyzed. Results show that it is the acting mechanisms of the added rare earth such as the purification of the interface, and then the increase of the interface bonding strength as well as the strengthening by nano-sized particles that result in the increase of the flexural strength and the fracture toughness of the ceramic tool material. Since the co-existing of both strong and weak interfaces, the toughening mechanisms like crack bridging, crack branching, crack defection and microcracking, etc. are noticeably increased and strengthened. Therefore, the fracture toughness of the Al2O3/(W,Ti) C ceramic tool material reinforced by rare earth is increased as a result of the interactions of several kinds of toughening mechanisms.

Key words: Ceramic tool material, Mechanical property, Rare earth element, Strengthening, Toughening