Interface wear behavior and its effects on the shear frictional sliding resistance in fiber-reinforced ceramics have been studied using SiC fiber (SCS-6)-reinforced A1203 matrix composite. Thin specimen pushout tests were performed and surface wear behavior of a protruded fiber was observed. Abrasive wear tracks along the sliding direction was observed at the surface of the SCS coating layer and the progress of abrasion was recognized with the increase of interface relative sliding. The abrasion was caused by a hard reaction product between the coating layer and the matrix. The effect of abrasion wear on the shear sliding resistance is discussed. A model, where hard particles on a harder surface sweep out a softer surface, is proposed and the pushout load-displacement curve is explained by the model. According to the model, the contribution of the wear to the pushout load Pab(u) is given as a function of fiber end displacement after onset of fiber pushout from the back surface, u, and the analysis suggests that the load strongly depends on the hard product shape, size, and density at the sliding surface. The success of the agreement indicates that the interface wear plays an important role in degradation of interface load transfer potential.
Citation: Acta Metallurgica
Pub Type: Journals
abrasion, alumina, ceramic matrix composites, fiber pushout, interfacial shear, plowing, resistance, wear