Diamond Abrasive
These are single diamond crystals from a diamond
impregnated drill bit. The high
refractive index of diamond results in very high relief, the width of the black band
at the edge of the particles.
Transmitted Off Crossed Polarized Light Illumination
Definition/Function:
Polycrystalline diamond abrasive has a conchordal fracture and is a prefered abrasive
for use in abrasive impregnated
metal saw blades and drills. Its irregular shape provides more area mechanically locking
the particle in the metal and
gives a sharper cutting surface. Single crystal diamond abrasive has a lower "cutting
speed" and a shorter life on the
tool because its tetragonal shape results in a very low surface area to bond to the
metal cutting tool and a rather dull
cutting surface.
Significance in the Environment:
Characteristic Features:
Diamond is isotropic, which distinguishes it from most other crystalline abrasives. Its
very high refractive index, 2.42,
distinguishes it from other isotropic abrasives such as garnet, slag, and glass. This
high refractive index results in
very strong relief at the edges of the particle.
Associated Particles:
References:
