Shock Physics and Autofrettage for Gun Barrels
Thanks to 20 years of experience in shock physics, as well as in laboratory launchers and high pressure technology (for autofrettage of gun barrels), THIOT INGENIERIE is now offering new services in terminal ballistics.
Thanks to 20 years of experience in shock physics, as well as in laboratory launchers and high pressure technology (for autofrettage of gun barrels), THIOT INGENIERIE is now offering new services in terminal ballistics:
- Perforation and impact testing
- Materials characterization in dynamic conditions
- Associated numerical simulation
Shock physics – terminal ballistics
The purpose of our shock physics laboratory is to study the mechanical behavior of various materials when impacted or subjected to high dynamic stresses as perforation for example.
Our capabilities in terms of experimental devices and in terms of numerical simulation allow us to be the right partner to analyze and investigate in shock physics for impacts, detonations, explosions, and more generally in events related to high strain rate.
We do have a long experience in this field and have been working on a very wide range of materials (concrete, composite materials, steels, aluminum alloys, explosives, ceramics, foams, ice…, for various applications.
We have also to point out the high level of instrumentation we commonly use:
- High-speed cameras (more than 10,000 fps)
- Laser interferometry, for pure shock physics studies
- Dynamic strain gauges, up to 24 channels, for structure response analysis
- Flash X-rays, two 150 kV units, 40ns of time exposure
- Laser barriers, switch pins, sheared wires, for fragment velocity measurement
- Large testing area (53 m3), compatible with large size targets
The experimental results (equation of state, damage law, mechanical behavior under shock conditions) are implemented in our numerical simulation software in order to improve the reliability of our simulations. At the same time, further investigation is carried out on the impacted targets (microscopy, crater analysis…) for a better understanding of the way the damage is generated during the shock.
We commonly use two different launchers:
- TITAN, 60, 100, or 220 mm gas launcher, for velocities up to 1 000 m/s
- HERMES, 12 mm two-stage launcher, for velocities up to 7 000 m/s
Tests of various types can be carried-out, such as:
- Terminal ballistics tests, with standardized fragments (STANAG, balls, cubes, bars, etc.)
- Reduced-scaled testing of natural or hazardous events, confirmed by full-scale numerical simulation
- Plate impacts, for mechanical characterization of materials stressed by shocks
- Taylor tests (direct, reverse, customized)
- Recovery of impacted materials, for post-impact analyses
Shock physics – detonation containment chambers
THIOT INGENIERIE supplies explosion or detonation containment chambers, and chambers designed for shock physics studies as well.
Containment and detonation chambers are usually designed to meet specific client’s requirements (multi-shot or single-shot type, gas explosion or explosive detonation, etc).
Our detonation containment forces can range from some grams to several Kg of equivalent TNT. Calculation codes used to design these explosion containment chambers are duly calibrated in THIOT INGENIERIE’s laboratory by material shock physics characterization testing.
Autofrettage machines for gun barrels
THIOT INGENIERIE supplies equipment and devices for working under very high pressure, including pressure generators, vessels, and more particularly autofrettage machines for gun barrels.
Double-stroke pumps are typically used for pressures up to 6,000 bars, and specific single-stroke generators are used for pressures up to 14,000 bars. High pressure valves, seals and other fittings are designed and manufactured by THIOT INGENIERIE in order to make maintenance very limited.
Machines are controlled thanks to a supervision, which ensures a greater operating safety level and a better repeatability of the pressurization process.
- Mechanical autofrettage or swaging process
- Electronic bore gauge especially designed for very long tubes