Nanodiamonds (NDs) have been widely explored for applications in drug delivery, optical bioimaging, sensors, quantum computing, and others. Room-temperature nanomanufacturing of NDs in open air using confined laser shock detonation (CLSD) emerges as a novel manufacturing strategy for ND fabrication. However, the fundamental process mechanism remains unclear. This work investigates the underlying mechanisms responsible for nanomanufacturing of NDs during CLSD with a focus on the laser-matter interaction, the role of the confining effect, and the graphite-to-diamond transition. Specifically, a first-principles model is integrated with a molecular dynamics simulation to describe the laser-induced thermo-hydrodynamic phenomena and the graphite-to-diamond phase transition during CLSD. The simulation results elucidate the confining effect in determining the material’s responses to laser irradiation in terms of the temporal and spatial evolutions of temperature, pressure, electron number density, and particle velocity. The integrated model demonstrates the capability of predicting the laser energy threshold for ND synthesis and the efficiency of ND nucleation under varying processing parameters. This research will provide significant insights into CLSD and advance this nanomanufacturing strategy for the fabrication of NDs and other high-temperature-high-pressure synthesized nanomaterials towards extensive applications.
Understanding the Laser-Matter Interaction and Plasma Dynamics in Nanosecond Pulsed Laser Shock Processing: A First Principle Study
Laser-matter interaction and plasma dynamic during laser shock processing determine the key parameters such as laser shock wave pressure and evolution during laser shock processing (LSP) process. A first-principle based model is critically important for elucidating the underlying mechanism and process optimization of the LSP process. The current study focuses on developing a theoretical model for the fundamental understanding of laser-matter interaction and plasma dynamics. The key physical parameters, such as electron and ion temperature, plasma density and shockwave pressure are predicted by this model and validated by experimental results.
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- Award ID(s):
- 1825739
- NSF-PAR ID:
- 10379355
- Date Published:
- Journal Name:
- Proceedings of the ASME 2019 14th International Manufacturing Science and Engineering Conference
- Volume:
- 2
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract A novel high‐temperature laser shock peening (HT‐LSP) process was applied to polycrystalline α‐SiC to improve the mechanical performance. HT‐LSP prevents microcrack formation on the surface while induces plastic deformation in the form of dislocation slip on the basal planes, which may be caused by the combination of high shock pressure and a lower critical resolved shear stress at 1000℃. A maximum compressive residual stress of 650 MPa, measured with Raman spectroscopy, was introduced into the surface of α‐SiC by HT‐LSP, which can increase the nanohardness and in‐plane fracture toughness of α‐SiC by 8% and 36%, respectively. This work presents a fundamental base for the promising applications of HT‐LSP to brittle ceramics to increase their plasticity and mechanical properties.
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1115/MSEC2019-2848
