The role of particle properties in the erosion of brittle materials

The erosion of a range of brittle materials (soda-lime glass, borosilicate glass, fused silica, boron carbide, partially stabilized zirconia, alumina and silicon carbide) with number of different erodent particle types (silicon, silica, alumina and silicon carbide) has been examined. The mechanisms of erosion depend upon the ratio of particle to target hardness. As this ratio falls towards unity, less damaging mechanisms of erosion dominate. Indentation-induced fracture models for erosion of brittle materials are not valid when this mechanism ceases to operate. The erosion rates decrease rapidly, and the velocity exponents of erosion rate increase, as the ratio of particle to target hardness decreases towards unity. The consequences of this in accelerated erosion testing are addressed.