PhD thesis: High-power laser initiation into detonation of secondary explosives
28/01/2022
Shock physics and detonics
In order to improve the safety of energetic systems, both in the civil and military domains, detonators containing only secondary explosives have been developed. Some of them are based on optical initiation, to further improve the safety by being immune to electromagnetic environments. These detonators present excellent priming power but are usually slower than their counterparts based on primary explosives. An alternative solution for faster optical initiation would be to use short-pulse high-power lasers. The plasma created by light-matter interaction can indeed generate a shock wave that will propagate inside the target material. It would be interesting to investigate whether this shock can be strong enough for inducing shock to detonation transition in the secondary explosive.
The objective of this PhD is to study the interaction between a high-power pulsed laser beam and a secondary explosive with/without additional elements, in order to generate a shock wave that will allow the transition into detonation of the energetic material. The PhD student will:
• Define the best secondary explosive/additional interaction material for effective light-matter interaction at high laser power.
• Characterize the shock generated in the energetic material when hit by a strong laser beam (first characterizations would be done on a mock explosive with same mechanical properties).
• Design an optimized system for inducing shock to detonation transition using numerical simulation tools.
• Perform a first proof-of-concept of a fast and safe all-secondary optical detonator.
• Publish research results at national and international conferences and journals.
This PhD work will be conducted in collaboration between the Shock Physics and Detonics (PCD) group of ISL and the Lasers, Plasmas et Procédés Photoniques (LP3) laboratory of the Aix-Marseille University. The PCD group has a strong background in energetics systems, among which opto-pyrotechnical detonators that have been transferred to the industry for military and civil applications. The LP3 laboratory furthermore brings its expertise on laser-matter interaction, laser-generated shock waves and their characterization. A shared funding between ISL and DGA is envisioned. Interested candidates (EU nationality is a requirement) are encouraged to apply for this position enclosing a detailed CV and a motivation letter.
