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A series of ATZ ceramies was prepared with appropriate addition of 4Y-ZrO2 to AT30(70wt. % Al2O3-30wt. % TiC) matrix. These ATZ ceramies possess good combination of fracture toughness (more than 12MPa·m1/2) and hardness(more than 20GPa) ,because they have good ability of exerting transformation toughening, microcracking toughing and dispersion toughening effects.1 Erosion MechanismOn the basis of analysis of microstructure and mechanical properties of ATZ ceramics, the erosion mechanisms of ATZ ceramies (under different erosive conditions) was studied thoroughly by Scanning Electron Microscopy. The results show that: (1)When ATZ are suffered by medium velocity impact, radial cracks and lateral cracks are induced; Then the interception of these cracks cause erosion of ATZ ceramies; (2)When ATZ are suffered by higher velocity impact,shoveling and strain fatigue erosion occur on the eroded surface of ATZ ceramies; (3)Va,Vb and Vc(the Threshold Velocities of the transition of above erosion mechanisms) are
These ATZ ceramies possess good combination of fracture toughness (more than 12 MPa · m1 / 2) and hardness (A) of ATZ ceramies was prepared with an appropriate addition of 4Y-ZrO2 to AT30 (70 wt.% Al2O3-30 wt.% TiC) more than 20 GPa), because they have good ability of exerting transformation toughening, microcracking toughing and dispersion toughening effects. 1 Erosion Mechanism On the basis of analysis of microstructure and mechanical properties of ATZ ceramics, the erosion mechanisms of ATZ ceramies (under different erosive conditions) was learned thoroughly by Scanning Electron Microscopy. The results show that: (1) When ATZ are suffered by medium velocity impact, radial cracks and lateral cracks are induced; Then the interception of these cracks cause erosion of ATZ ceramies; (2) When ATZ are suffered by higher velocity impact, shoveling and strain fatigue erosion on the eroded surface of ATZ ceramies; (3) Va, Vb and Vc (the Threshold Velocities of the transition of above erosio n mechanisms) are