A FINE AL2O3-TIC-CO CERAMIC AND ITS EROSION BEHAVIOR

In this paper, a new powder processing method is described. A layer of metal cobalt is successfully coated on the surface of fine Al2O3 and TiC powders by chemical deposition. The mixture of the two kinds of Co -coated powder (about 70 wt% Al2O3-Co + 30 wt% TiC-Co) is hot pressed into a fine Al2O3-TiC-Co (ATC) ceramic. Scanning electron microscopica l observation is employed to investigate fracture sections and erosion surfaces. Comparing with AT30 (70 wt% Al2O3 + 30 wt% TiC) ceramic, it s high fracture toughness and strength with relatively fine microstruc ture are believed to make it more resistant than AT30 ceramic against particle erosion under different impact velocity and impact angles. Th e SEM images show that the worn surface exhibits shallow detaching, mi crocracking and plastic deformation. Erosion wear resistance depends o n not only mechanical properties, but also microstructure.