High velocity erosion of CVD diamond coatings by diamond particles

Abstract

This paper describes a study of the damage mechanisms of diamond coatings subjected to high velocity erosion by diamond particles. The coatings were tested using 70/80 mesh natural and synthetic diamond particles at a velocity of 300 m s−1 and the eroded coatings examined by surface profilometry and scanning electron microscopy. The results have shown that the impacting diamond particles generate radial and lateral cracks in the coatings, and material is removed following the intersection of these cracks with each other and with the surface. The greater strength of the synthetic diamond over the natural diamond is demonstrated by the shorter time to failure of the coating when eroded by the synthetic particles.