Dynamic Response of Reactive Materials

Dynamic response of reactive materials

Reactive materials such as metal powders, thermite mixtures, mixed composites, and nano-energetics are an emerging class of energetic materials, whose thermochemical responses are very different from hydrocarbon-based energetic materials. In order to evaluate the performance and reliability of reactive materials, one needs to know the dynamic responses over a wide range of time scales; for example, ms for intermetallic reactions, ms-ms for metathesis reactions, ms for metal combustion, and ns for detonation. Hence, the goal of this project is to understanding dynamic responses of reactive materials, particularly, via resolving the structural and chemical evolution of reactive materials under rapidly propagating, exothermic reactions, using various time-resolved spectroscopic and diffraction technologies.  The development of new enabling technologies are also of interest to this project.

Recently, we have developed time-resolved synchrotron x-ray diffraction at the APS, utilizing a large 2D x-ray detector and a fast running x-ray chopper. This new technique has been applied to get real-time structural information during metal combustions and intermetallic reactions, as shown in the figure. It shows the time-resolved x-ray diffraction patterns obtained during Zr combustion with a 30 ms time resolution. This result reveals several significant facts: (i) the combustion occurs from molten phase of Zr – the first direct evidence observed. (ii) The combustion process is substantially more complex than what we have typically assumed previously (Zr + O₂ -> ZrO₂). It undergoes a series of transformations from a-Zr -> b-Zr -> liq-Zr -> ZrO -> Zr₃O -> ZrO₂, many of these transformations are exothermic, thus, important for understanding the energetics of Zr combustion. (iii) quantitative chemical – time information regarding the combustion. Note that these are critical data to develop/validate thermochemical models. In fact, many thermochemical libraries currently used have a limited data basis for reactive materials and incomplete descriptions of metal combustions.

WSU is a leading institute for high-pressure research both in static and dynamic research, with a wide range of enabling capabilities such as laser-heated DAC, dynamic-DAC, micro impactor, laser ablator, and various gas guns – all coupled with cutting-edge time-resolved spectroscopy, high-speed microphotography, time-resolved spectro-pyrometry, and the third-generation synchrotron x-ray source at the APS.

 

 

Our research has been in support of:

• ARO (W911NF-14-1-0233): Dynamic Responses of Reactive Metal Alloys
• DHS (2013-ST-061-ED0001): ALERT Center for Energetic Materials
• DARPA (W911NF-09-C-0033): Reactive Materials Structure: Chemical Performance (co-PI with four others, Completed, 2009-2011)

 

References:

• Time-resolved x-ray diffraction of reactive solids under dynamic loadings, Choong-Shik Yoo, J. Phys.: Conf. Ser., in print (2015)
• Probing Dynamic Crystal Growth of Compressed Hydrogen using Dynamic-DAC, Time-Resolved Spectroscopy and High Speed Microscopy, Dane Tomasino and Choong-Shik Yoo, J. Phys. Con. Ser. 500, 032019 (2014).
• Time-resolved X-ray Diffraction Across Water-Ice VI/VII Transformations using Dynamic-DAC, Jing-Yin Chen, Minseob Kim, Choong-Shik Yoo, and William Evans, J. Phys. Conf. Ser. 500, 142006 (2014).
• Solidification and Crystal Growth of Highly Compressed Hydrogen and Deuterium: Time-Resolved Study under Ramp Compression in Dynamic-Diamond Anvil Cell, Dane Tomasino and Choong-Shik Yoo, Appl. Phys. Lett. 103, 061905 (2013).
• Dynamic Responses of Reactive Metallic Structures under Thermal and Mechanical Ignitions, Haoyan Wei and Choong-Shik Yoo, J. Mater. Res. 27, 2705 (2012).
• Kinetics of Small Single Particle Combustion of Zirconium Alloy, Haoyan Wei and Choong-Shik Yoo, J. App. Phys. 111, 023506 (2012).
• Oxygen-Diffusion Limited Metal Combustions in Zr, Fe and Ti Foils: Time-Resolved X-ray Diffraction Studies, Haoyan Wei, Jing-Yin Chen and Choong-Shik Yoo, J. App. Phys. 111, 063528 (2012).
• Time- and angle-resolved x-ray diffraction to probe structural and chemical evolution during Al-Ni intermetallic reactions, ChoongShik Yoo, Haoyan Wei, Jing-Yin Chen, Guoyin Shen, Paul Chow, and Yuming Xiao, Rev. Sci. Instrum. 82, 113901 (2011).