Explosives And Propellants Flashcards
What is ASA (F2 det) composition made up of and what are the percentages?
Lead azide 68%
Lead styphahnate 29%
Aluminium powder 3%
What are the two types of explosive initiators?
Detonators
Igniters
What is the abbreviation for composition explosives?
CE
Propellants are classified as low explosive, name another two
Gun powder
Pyrotechnics
What is the definition of HE?
Any explosive once initiated decomposes almost instantly to its molecular structure by the passage of a detonation wave through it, with a subsequent production of heat and gases and liberation of great energy
What is the Definition of primary explosives/iniator?
Substance or mixture of substances used to initiate a detonation or a burning reaction
What are the required characteristics of a primary explosive?
Stability over long periods
Optimum sensitivity to applied stimulus
Optimum output of the required kind
Compatibility with materials
What are the primary explosive compounds?
Lead azide
Lead styphnate
Lead dinotro rescorcinate
PETN
Von hertz mixtures
ASA compounds
What are the purposes of HE additives?
Increase sensitivity
Improve stability
Increase blast effects
Improve moldability
Decrease sensitivity
(SSBMS)
Two categories of propellants ?
Liquid
Solid
What are the main propellant types based on a collidal system of manufacture ?
Single, double and triple based.
What are all service propellants based on?
Nitrocellulose.
What is the purpose of dark ignition?
Tracers not visible by firer until projectile travelled approx 100-200m
To avoid observation of exact location
Avoid dazzling the gun layers
what are three things that effect the burn rate of propellant?
Propellant composition
Shape of propellant
Size of propellant
What produces the red in smoke and signals?
Strontium nitrate
What produces the yellow in smoke and signals?
Sodium nitrate
What produces the green in smoke and signals?
Barium nitrate
Describe the definition of an Explosion
The violent and rapid decomposition of energetic material to produce energy (heat) and gas which will lead to violent pressure rupturing of any confining structure.
What are the 4 pyrotechnic effects?
Heat
Light
Smoke
Sound
Describe deflagration -
Technical term describing SUBSONIC combustion that usually propagates through thermal conductivity. (Hot burning material heats next layer of cold & ignites)
Describe detonation -
Involves a SUPERSONIC exothermic front acceleration though a medium that drives a shock front propagating directly in front of it.
What are the requirements for propellants?
Give regular ballistics
Not produce excessive flash or smoke
Must not cause undue erosion
Must be relatively easily ignited
Must be stable for storage under worldwide conditions
What are the 6 types of fuel used in Fuel Air Explosives?
Acetylene
Butane
Ethylene Oxide
Kerosene
Propylene Oxide
Aluminium
What are the three phases of blast ?
Shock Front
Positive Phase
Negative Phase
What are the three types of explosions?
Physical
Chemical
Nuclear Explosion
What does guncotton consist of ?
Nitrocellulose, Nitric Acid and cotton fibres.
What does ballistite consist of?
camphor(wax), nitroglycerine, nitrocellulose.
What does cordite consist of ?
Nitroglycerine, nitrocellulose and petroleum jelly.
What are the requirements for military explosives ?
Performance
Sensitivity
Stability & behaviour in storage
Water resistance
Consistency
Thermal behaviour
What are some of the ways to initiate Explosives?
Direct Heat / Flame
Percussion & Stabbing
Friction
Electrical
Shock Waves
Describe Brisance -
The shattering effect of explosives.
What are the two main types of smoke compositions ?
Bergers
White Phos
what is the acronym for Cyclotrimethylenetrinitromine?
RDX
what is the acronym for Pentaerythritol
Tetranitrate?
PETN
what is the acronym for Cyclotetramethylenetetranitramine?
HMX
what is the English word for Trinitrophenol?
PICRIC ACID
what are the degressive propellant shapes?
cord
flake
strip/ribbon
what are the neutral propellant shapes?
tubular
cogged
star centre
what are the progressive propellant shapes
rosette
multi tubular
what makes up the Australian propellant code?
first digit - physical shape
second digit - deterrent coating
third digit - indication of single or double based
what are the advantages to WP?
immediate effect on burning
excellent screen produced
no priming or ignition devices required
what are the disadvantages to the berger composition?
requires special priming and ignition devices
effective screen takes longer to build up
what are the two main types of berger compositions?
-zinc powder and zinc oxide with carbon tetrachloride absorbed on kieselguhr or magnesium carbonate.
-Zinc oxide, zinc powder and hexachlorethane.
what are the three types of explosion?
Physical
Chemical
Nuclear
what are the four types of blast pressure?
Dynamic Pressure
Incident Pressure
Quasi Static Pressure
Reflected Pressure
What is the basic principle of FAE?
Consists of creating an aerosol cloud of a
fuel air mixture, which is then initiated to
create an explosive effect, not a fire such as
napalm.
what are the factors that effect VOD?
density of charge
charge diameter
degree of confinement
strength of detonator
solid propellants can be divided in two types, what are they?
colloidal- single, double and triple based
composite
what are the advantages to double based propellants?
Easily ignited
Higher energy rating than single base
Higher flame temperature
Higher burning rate
what are the additives that can be added to propellants?
Stabilisers
Plasticisers
Coolants
Surface moderants
Surface lubricants
Flash inhibitors
De coppering agents
Anti wear additives
What are the ideal properties of smoke?
Immediate in effect
Unaffected as far as possible
Persistent
Non anti personnel
Non incendiary
