WEIBULL STRENGTH DISTRIBUTIONS AND FRACTURE CHARACTERISTICS OF ABRASIVE MATERIALS

The Weibull strength distributions and fracture characteristics of thr ee abrasive grains, brown corundum, white corundum and green silicon c arbide, are investigated. The effects of the surface defects from crus hing and the inherent microcracks from processing prior to crushing on fracture strengths and characteristics of the abrasive grains are dis cussed together with SEM observations. A novel proof-testing has been carried out in terms of low energy ball milling so that survived abras ive grains have improved strength characteristics. Strength distributi ons before and after the proof-testing have been compared. It is concl uded that the strength of larger grains is strongly influenced by surf ace defects due to crushing, and the strength of smaller grains is mor e relevant to the inherent processing microcracks and pores formed dur ing the manufacturing process prior to crushing. The influence of proc essing conditions, such as fusing and sintering, on strength distribut ions of the brown corundum is also discussed.