The explosive
power of a
compound can be judged using two criteria, the
detonation rate, which describes the spread of the shock wave generated, and the physical
density of the
material, which is a guide to the
energy concentration of the material.
One of the most powerful explosives known is
hexanitroisowurztitane also known as 'CL20'. This has a detonation rate of 9380 m s
-1, and a density of 1.98 g/cm. The shock wave it produces expands through air at 21,000
miles per hour! (The
speed of sound is only 675 miles per hour).
HMX, tetramethylene tetranitramine or octagen is the most powerful commercially available explosive and has a detonation rate of 9110 m s
-1, with a density of 1.89 g/cm.
TNT has a detonation rate of 6930 m s
-1 and a density of 1.63 g/cm.
The cheapest explosive, which has 80% of the market share is simply a mixture of
diesel oil and ammonium nitrate an is known as
ANFO.