28 - Chemical Explosives and Power Index

Question 1

Characteristics of military explosives

Answer 1

• Availability
• Cost
• Sensitivity
• Stability
• Power
• Brisance (Measure of shattering effect)
• Density
• Volatility
• Toxicity

Question 2

When an explosive detonates it turns into:

Answer 2

1. Gasses
2. Heat
3. Residue

Question 3

An explosive’s strength can be estimated by:

Answer 3

1. OB% (Oxygen Balance)
2. Gas production
3. Release of heat (Q)

Question 4

What is an explosion?

Answer 4

Rapid & violent release of energy
1. Mechanical
- Over-pressurized container
2. Chemical
- Change Chemical Bonds
3. Nuclear
- Change of Nucleus of Atoms

Question 5

Categories of Chemical Explosives

Answer 5

1. Low explosives
   - Deflagration: subsonic wave propagation/burning
2. High explosives
   - Detonation: supersonic shock wave propagation
   - 1000-8500 m/s

Question 6

Uses of High Explosives

Answer 6

• Generally insensitive
• Normally employed in warheads
  1. Primary high explosives
• Used as detonators
  2. Secondary high explosives
• Used as booster & main charges of warheads

Detonation rates of 1000-8500 m/s

Question 7

Why an explosive train?

Answer 7

For Safety

Question 8

What is Oxygen Balance (OB)?

Answer 8

Degree to which explosive can be oxidized
- Desired OB% = 0
- Oxygen Deficient < 0
- Oxygen Rich > 0

Question 9

What is Explosive Power?

Answer 9

Q x V_STP
Chemical explosive yield is proportional to both thermal and mechanical effects

Thermal = Heat of Explosion
Mechanical = Vol. of Gases

Question 10

What is Power Index (PI)?

Answer 10

Comparison of explosive power relative to other explosives

TNT is the normal reference