'Ammonal' is an explosive made up of
ammonium nitrate,
trinitrotoluene, and
aluminium powder mixed in a ratio of roughly 22:67:11.
The ammonium nitrate functions as an
oxidizer and aluminium as a power enhancer. To some extent the aluminium makes it more sensitive to detonation. The use of the relatively cheap ammonium nitrate and aluminium make it a replacement for pure TNT.
The mixture can suffer because ammonium nitrate is highly
hygroscopic. Ammonal burns vigorously when open to the air, but detonates when confined inside some form of casing.
Detonation velocity is 4,400 m/s.
History
From early 1915 the
British Army employed ammonal for their mines during the First World War eg at
Hawthorne Ridge during the
Battle of the Somme. British ammonal comprised a mixture of 65% ammonium nitrate, 15% TNT, 17% coarse aluminum and 3% charcoal by weight. Three of the mines used at the
Battle of Messines which were exploded at the start of the
Third Battle of Ypres contained 30,000 lbs (over 13.6
metric tons) of ammonal, the fourth contained 20,000 lbs (over 9
metric tons). Ammonal used for military mining purposes was generally contained within metal cans or rubberised bags to prevent moisture ingress problems.
Ammonal remains in use as an industrial explosive. Typically, it is used for
quarrying or
mining purposes.
See also
★
Amatol