Controlling Shock-Induced Energy Release Characteristics of PTFE/Al by Adding Oxides

Area of Science:

• Materials Science
• Energetic Materials
• Shock Physics

Background:

• Polytetrafluoroethylene (PTFE)/aluminum (Al)-based energetic materials offer significant application potential.
• Controlling shock-induced energy release is crucial for optimizing performance and safety.

Purpose of the Study:

• To investigate the influence of various oxides (bismuth trioxide, copper oxide, molybdenum trioxide, iron trioxide) on the shock-induced energy release characteristics of PTFE/Al energetic materials.
• To understand the mechanisms by which oxides modify energy release under ballistic impact.

Main Methods:

• Ballistic impact experiments were conducted at velocities ranging from 735 to 1290 m/s.
• Overpressure characteristics (peak, duration, impulse) were measured to quantify energy release.
• An analytical model was developed based on experimental data.

Main Results:

• Oxides effectively controlled energy release, influenced by impact velocity and oxide properties.
• PTFE/Al/MoO₃ exhibited a 1.99 times higher quasi-static overpressure peak (0.1190 MPa) compared to PTFE/Al (0.0598 MPa) at 735 m/s.
• The analytical model identified apparent activation energy and impact shock pressure as dominant factors.

Conclusions:

• Oxides enhance energy release primarily after shock wave unloading.
• The chemical and physical properties of thermites play a role in controlling energy release.
• Findings provide guidance for designing PTFE-based energetic and reactive materials, particularly concerning oxide additives.