5 Testing of materials for reactivity with liquid
oxygen on mechanical impact
Approximately 0.5 g of the divided sample is placed into a sample cup, made of
0.01 mm copper foil. Liquid oxygen is poured into the cup over the sample until it
is immersed in liquid. The sample is then exposed to the mechanical impact of a
plummet with a mass of 76.5 kg. The drop height and in this way the impact energy
of the plummet can be varied.
A flame and a more or less strong noise of an explosion usually indicate a reaction
of the sample with liquid oxygen. In varying the drop height of the plummet,
the impact energy, at which no reaction occurs, is determined in a series of ten
The material is not compatible with liquid oxygen, if reactions occur at impact energies
of 125 Nm or less.