Studying the stability and performance of energetic materials across their lifespan
LLNL scientists explore dynamic phenomena—ranging from nanoseconds to years—to ensure that materials meet safety and performance criteria from cradle to grave. By continuously pushing the boundaries of existing techniques, we can provide higher-fidelity surveillance of current energetics and intelligent design of future components. As we expand our understanding of how aging impacts performance, we can rapidly down-select options for more age-resistant components, test promising new designs, and create system-level solutions.
Examples of our aging and compatibility assessments include:
- Executing accelerated aging studies to analyze material changes due to environmental conditions.
- Developing and deploying cutting-edge diagnostics to rapidly assess material changes and inform model development.
- Performing high-fidelity tests to quantify material performance as a function of age and stress.
- Developing and employing powerful, age-aware predictive models.
Key Capabilities
LLNL’s multidisciplinary research teams study material aging from diverse perspectives. The foundation of the research involves studying how prolonged exposure to environmental conditions changes material properties and performance.
- The reaction, sorption, transport, and chemo-mechanical modeling tool, developed at LLNL, supplies mechanistic-based predictions of vapor/gas concentrations and reactions between materials in each system. The model enables service life assessments that explore the full landscape of variables, ranging from environmental conditions to uncertainties in material properties and design.
- Age-aware performance models predict changes in materials and components, based on an analysis of microstructural features. Using a nondestructive, noncontact metrology technique known as optical profilometry, scientists collect two-dimensional images before and after aging experiments. With machine learning and computer vision techniques, changes in physical features are characterized and used to identify phenomena that that might impact performance as the material ages.
- Rigorous evaluation of material outgassing provides essential information for system-level material compatibility assessments. Outgassed species may be signatures of material degradation, may affect other materials in the system, or may be harmless. Characterization of the species, quantification of thermodynamic and kinetic parameters, and determination of their origins enables the development of a system-level gas-spectrum prediction that is age-informed—making interpretation of gas data from surveillance easy and robust.
Mission Impact
Our research provides the foundational knowledge that enables our national security partners to:
- Design robust energetic systems that meet performance requirements over the service lifetime.
- Conduct ongoing surveillance of components and systems to determine end-of-life reliability.
- Leverage an advanced understanding of energetic materials when investing in future design and production solutions.
Featured Collaborations
LLNL scientists collaborate with colleagues at Sandia National Laboratories to conduct joint compatibility tests of materials used in components and systems. We test materials in a shared headspace environment to ensure the cross-compatibility of materials used across design agencies. We also collaborate with academic institutions in material informatics and data science.
Related Resources
LLNL’s Thermal Aging Facilities house tools used to conduct accelerated, multi-material aging experiments. The materials are placed in sealed, pressurized vessels to thermally accelerate chemical reaction kinetics, enabling scientists to evaluate the long-term compatibility of materials.
The High Explosives Laser Imaging Optical System, developed at LLNL, uses ultrafast imaging technology to capture high-speed images of detonators and initiators. By analyzing these images, scientists can evaluate detonator designs, validate hydrodynamic models of detonation phenomena, and analyze how material aging affects detonator performance—providing insight regarding the long-term performance of components and informing future design decisions.
Advanced analytical instrumentation, such as liquid chromatography and diode array detector chromatography, enable researchers to quantify the chemical composition of materials, identify compounds that are signatures of degradation, and determine the effects of long-term material aging.