Plastic Deformation of Al 2 O 3 During Abrasion

X‐ray diffraction line broadening examination of the debris produced by abrasion of polycrystalline Al 2 O 3 on a 320‐grade diamond‐impregnated lap showed that heavy plastic deformation is associated with the abrasive process. Annealing of the debris resulted in an increase in crystallite size at temperatures >800°C but only minor changes in microstrain. This behavior contrasts with the large reduction in microstrain reported for ball‐milled Al 2 O 3 with similar initial crystallite size. The results are consistent with recovery during formation of the debris particles. A transient temperature of 900° to 1200°C was estimated from the plastic work done, assuming that material is removed by a mechanism similar to that observed in the abrasion of metals.