Ignition Threshold Research Articles

Delivering laser performance conditions to enable fusion ignition, and beyond at the National Ignition Facility

On December 5th, 2022, controlled fusion ignition was demonstrated for the first time at the National Ignition Facility (NIF), a major achievement in the field of Inertial Confinement Fusion (ICF) requiring a multi-decadal effort involving broad national and international collaborations. To drive the fusion ignition reaction with the compressed fuel capsule, that yielded 3.15 MJ of nuclear energy [1], the NIF laser delivered a high-precision pulse shape with 2.05 MJ of ultra-violet (UV) laser energy and a peak power of 440 TW. This laser energy was an increase of ∼8 % compared to that delivered on the previous “threshold of ignition” record yield experiment (1.37 MJ of yield for 1.89 MJ of laser energy) on August 8th, 2021 [2].We explain how the results of our extensive research in laser technology and UV optics damage mitigation led to major improvements in the NIF laser, enabling this energy increase along with additional accuracy, precision, and power balance enhancements. Furthermore, we will discuss on-going efforts that have enabled operations at 2.2 MJ of UV energy as well as potential new initiatives to push the laser performance –accuracy and delivered energy– to even higher levels in the future as previously demonstrated on a small subset of NIF beams [3].

Construction of Fe Nanoparticles Interfacial Layer on Micron Al Surface: Boosting the Efficient Energy Release of High-Energy DAP-4 as a Gradient Catalyst.

The high-energy (H2dabco)[NH4(ClO4)3] (DAP-4) with excellent energetic performance attracts wide attention from researchers. The investigation of its interaction with the Aluminum (Al) is of great importance. However, the higher ignition threshold of DAP-4 and the dense oxide layer (Al2O3) of Al severely limit the energy release efficiency of Al/DAP-4. In this study, a new idea to is first proposed to improve and adjust the thermal decomposition and combustion performance of Al/DAP-4 by constructing a highly dispersed iron (Fe) nanoparticle interfacial layer. It acts as a gradient catalyst to promote the thermal decomposition and combustion of DAP-4 and Al, and it also act as an oxygen transport channel to promote the contact and reaction of oxidizing gases with the internal reactive Al powder. It reduces the thermal decomposition temperature of Al@Fe-3/DAP-4 from 386.30 °C (Al/DAP-4) to 349.48 °C and leads to the vigorous combustion. Theoretical calculations show that Fe nanoparticle interfacial layer can facilitate the transport of oxygen through the established oxygen transport channels, and it can also significantly improve the energetic properties of Al@Fe-3/DAP-4 composites. In conclusion, the new approach is proposed to improve the performance of metal fuel/oxidizer composites by constructing interfacial layers, which is expected to promote their practical applications.

Wildfire-vegetation-climate-human interactions in the central Taiwan region during 17.3–2.0 cal kyr BP, inferred from sediments of Toushe Basin

In this study, a long-term relationship amongst wildfire, vegetation, climate, and human in the central Taiwan region, spanning from 17.3 to 2.0 cal kyr BP, is explored. To investigate this relationship, multiple proxy approaches were employed, including charcoal (CHAR and fire frequency), pollen data (Liew et al., 2006), magnetic susceptibility, and the carbon isotopic composition of organic carbon, along with the elemental ratio of total organic carbon to total nitrogen in the core sediments of the Toushe Basin, central Taiwan. From 17.3 to 14.5 cal kyr BP, the Toushe Basin experienced drier climate conditions, leading to high-intensity fires and reduced area of wetland. Between 14.5 and 11.5 cal kyr BP, a wetter climate corresponded with low-intensity fires and an increase in tree prevalence. From 11.5 to 5.0 cal kyr BP, the climate remained relatively stable with peaks of extreme wet phases, with frequent low-intensity fires promoting herbaceous plant growth. During the period from 5.0 to 2.0 cal kyr BP, wetter conditions persisted, but increased human activities likely intensified high-intensity fires, resulting in reduced tree and herbaceous plant populations and an expansion of wetlands, leading to complex impacts on the region's ecological dynamics. The pollen diversity index (PDI) and pollen richness index (PRI) showed that ecological diversity in the Toushe Basin decreased with high-intensity fires and increased with low-intensity fires, highlighting the complex interactions between natural and human factors during 17.3–2.0 cal kyr BP. In addition, this study showed a strong link between El-Niño events and increased wildfire activity in the Toushe Basin. El-Niño conditions, with reduced rainfall and increased dryness, likely heightened wildfire frequencies and intensity by lowering moisture levels and ignition thresholds. Increased lightning during these periods further exacerbated wildfires. This connection highlights El-Niño ‘s role in driving high-intensity fires, impacting the region's vegetation and ecological dynamics.

Theoretical and simulation analysis for R290 leakage from split-type air conditioners

Propane (R290) is a promising refrigerant for split-type household air conditioners with the advantages of energy saving, environmentally friendliness and low charge. Nevertheless, the large scale use of R290 has been hindered by its high flammability. The potential fire hazards can be relieved by reducing R290 releasable charge, and numerous methods have been put forward. In the authors’ previous papers, the method of refrigerant pump-down was proposed and a mathematical model of critical releasable charge (CRC, ignition threshold of leakage) was developed by dimensional analysis, but it is difficult to reflect the actual physical process of R290 dispersion. To reveal the leakage and dispersion mechanism of R290, a new numerical model of CRC is developed based on mechanism analysis in this work, in which the turbulent jet model, Coanda effect and dimensional analysis are involved. The predicted CRCs agree well with experimental and simulated data. Besides, the influence of indoor air speed with its direction parallel to the IDU panel on R290 concentration field is investigated by computational fluid dynamics (CFD) under different releasable charges. It is found that there is a transition value of air speed, below which the fire hazards decrease greatly with the increase of air speed, on the contrary, when the air speed is above the transition value, raising air speed has little impact on fire hazards.

Use of tritium-rich fuel to improve the yield of layered deuterium/tritium inertial fusion capsules

In deuterium–tritium (DT) ice layered implosions, nearly all hot spot mass at peak burn comes from the dense fuel. Accurate prediction of the fuel mass ablation, including the enthalpy associated with mass inflow into the hot spot from the dense fuel, is essential to understanding the energetics and ignition of the hot spot in layered implosions. A recently published boundary layer analysis (Daughton et al., 2023) indicates a faster mass ablation rate than in previous analyses of layered implosions. Inclusion of this effect provides a better match to simulations and leads to a new ignition threshold where the temperature of the dense fuel plays a critical role. This analysis motivates possible new directions for improved capsule performance. Here, the authors present evidence in support of one such approach: the use of tritium-rich ice to decrease 14 MeV neutron scattering and heating of the dense fuel, resulting in less mass ablation and more robust burn of the hot spot. It is found from numerical simulations that despite a less favorable D:T ratio in the ice, the use of a 40:60 D:T ratio leads to an increase in capsule yield of 17% percent compared with that of a 50:50 D:T ratio fuel for capsules resembling those of the recent N210808 ignition experiment on the NIF (Abu-Shawareb et al., 2022) and an increase of 74% compared with that of a 60:40 D:T ratio fuel capsule. These results are potentially important for modeling all layered implosions, since some degree of DT fractionization may arise naturally during the beta layering process. In addition, this physics is important for the feasibility of high-gain capsule designs that seek to minimize tritium usage, as in some inertial fusion energy concepts.

Modeling ablator defects as a source of mix in high-performance implosions at the National Ignition Facility

Recent indirect drive inertial confinement fusion implosions on the National Ignition Facility (NIF) [Spaeth et al., Fusion Sci. Technol. 69, 25 (2016)] have crossed the threshold of ignition. However, performance has been variable due to several factors. One of the leading sources of variability is the quality of the high-density carbon (HDC) shells used as ablators in these experiments. In particular, these shells can have a number of defects that have been found to correlate with the appearance of ablator mix into the hot spot and a degradation in nuclear yield. These defects include pits on the ablator surface, voids in the ablator bulk, high-Z debris from the Hohlraum wall that adheres to the capsule surface, and finally the inherent granular micro-structure of the crystalline HDC itself. This paper summarizes high-resolution modeling of each of these mix sources in two recent high-performance NIF implosion experiments. The simulated impact from a range of individual capsule defects is found to be broadly consistent with the trends seen in experiment, lending credence to the modeling results and the details of the mixing process that they reveal. Interestingly, modeling of the micro-structure inherent to HDC shows that this perturbation source results in considerable mixing of the deuterium–tritium fuel with ablator material during the implosion. The reduction in fuel compression from this mix results in an approximately factor of two reduction in neutron yield in current implosions and emphasizes the importance of mitigating this significant performance degradation.

Fabrication of Al@AIH@PVDF metastable composite film with enhanced laser ignition ability and combustion performance

Laser ignition technology has garnered significant attention for energetic materials in recent years, offering advantages over traditional electrical initiation methods, notably in mitigating issues related to stray currents and electromagnetic interference. Moreover, it can facilitate multi-point synchronous ignition. However, the persistent challenges of high ignition thresholds and delays in energetic materials necessitate effective resolutions. In this study, we address these challenges by converting the inert Al2O3 layer on the surface of aluminum powder into the active compound Aluminum Iodate Hexahydrate ([Al(H2O)6](IO3)3(HIO3)2, AIH) to prepare an Al@AIH@PVDF energetic composite film (ECF) with the aim of reducing the laser ignition threshold and delay of Al@PVDF ECF. The Al@AIH@PVDF ECF was synthesized through a simple wet chemistry method and a rapid evaporation process suing a simple, environmental-friendly, and cost-effective way. Differential scanning calorimetry-thermogravimetric analysis (DSC-TG) results demonstrate a lower exothermic reaction temperature (161 °C) and higher heat release (2900 J g−1) for Al@AIH@PVDF ECF. Laser ignition tests reveal a reduced laser ignition delay (11 ms) and threshold (1.59 J cm−2) for Al@AIH@PVDF ECF. Combustion experiments showcase elevated combustion flame temperature (3090 K), burning rate (4.11 cm s−1), and smaller condensed combustion products, while effectively igniting CL-20. Pressure tests indicate higher maximum combustion pressure (3.24 MPa) and pressure rise rate (4.05 GPa s−1) for Al@AIH@PVDF ECF. Finally, the reaction process and mechanism of Al@AIH@PVDF ECF was also investigated and proposed.

Moisture thresholds for ignition vary between types of eucalypt forests across an aridity gradient

ContextQuantifying spatial and temporal variations in landscape flammability is important for implementing ecologically desirable prescribed burns and gauging the level of fire risk across a landscape. Yet there is a paucity of models that provide adequate spatial detail about landscape flammability for these purposes.ObjectivesOur aim was to quantify spatial and temporal variations in ignitability across a forested landscape. We asked: (1) How do fuel moisture and meteorological variables interact to affect ignitability? (2) Do fuel moisture thresholds for ignition vary across a gradient of forest types? (3) How does the spatial connectivity of ignitable fuel vary over time? (4) How could an ignitability model be used to inform fire management decision-making?MethodsWe conducted field-based ignition tests with flaming firebrands over three fire seasons. Ignitions were attempted across a range of moisture and meteorological conditions at 15 sites in eucalypt forest in south-eastern Australia. Structural equation modelling and generalized linear models were used to quantify relationships between ignitability, aridity, fuel moisture and weather.ResultsThe strongest predictors of ignitability were the moisture content of dead near surface fine fuel and in-forest vapour pressure deficit. Ignition thresholds for both varied across an aridity gradient. Dense forests (i.e., wet and damp eucalypt forests) needed drier fuel and drier in-forest atmospheric conditions to ignite than sparser forests (i.e., shrubby foothill forest).ConclusionOur modelling of ignitability could inform fire planning in south-eastern Australia and the methodology could be applied elsewhere to develop similar models for other regions. Days with consistently high ignitability across the landscape are more conducive to the development of large wildfires whereas days when ignitability is spatially variable are more suitable for prescribed burning.

Optimization of Fuel Injection Process and Structural Analysis

In order to solve the problem of precise and controllable ignition fuel injection point in the process of UCG, this paper proposes a process method of presetting the ignition agent. The method achieves the purpose of improving the ignition success rate by increasing the downhole ambient temperature and reducing the ignition threshold. By simulating and analyzing the fluid properties of the fuel in the pipeline, the velocity and dynamic pressure at the outlet of the pipeline under different initial velocities are obtained. The results show that the outlet velocity, dynamic pressure and initial velocity have an irregular curvature relationship. As the initial velocity increases, the outlet velocity and dynamic pressure continue to increase. After calculation, the relationship between the exit speed (Y) and the initial speed (X) is Y=-0.5069X2+2.0909X+5.0624. Therefore, long-distance injection is not conducive to the successful ignition of the fuel downhole.

Diurnal fuel moisture content variations of live and dead Calluna vegetation in a temperate peatland

The increasing frequency and severity of UK wildfires, attributed in part to the effects of climate change, highlights the critical role of fuel moisture content (FMC) of live and dead vegetation in shaping wildfire behaviour. However, current models used to assess wildfire danger do not perform well in shrub-type fuels such as Calluna vulgaris, requiring in part an improved understanding of fuel moisture dynamics on diurnal and seasonal scales. To this end, 554 samples of upper live Calluna canopy, live Calluna stems, upper dead Calluna canopy, dead Calluna stems, moss, litter and organic layer (top 5 cm of organic material above mineral soil) were sampled hourly between 10:00 and 18:00 on seven days from March-August. Using a novel statistical method for investigating diurnal patterns, we found distinctive diurnal and seasonal trends in FMC for all fuel layers. Notably, significant diurnal patterns were evident in dead Calluna across nearly all sampled months, while diurnal trends in live Calluna canopy were pronounced in March, June, and August, coinciding with the peak occurrence of UK wildfires. In addition, the moisture content of moss and litter was found to fluctuate above and below their relative ignition thresholds throughout the day on some sampling days. These findings underscore the impact of diurnal FMC variations on wildfire danger during early spring and late summer in Calluna dominated peatlands and the need to consider such fluctuations in management and fire suppression strategies.

The initiation of smouldering peat fire by a glowing firebrand

Background Wildfires represent a significant threat to peatlands globally, but whether peat fires can be initiated by a lofted firebrand is still unknown. Aims We investigated the ignition threshold of peat fires by a glowing firebrand through laboratory-scale experiments. Methods The oven-dried weight (ODW) moisture content (MC) of peat samples varied from 5% ODW to 100% ODW, and external wind (ν) with velocities up to 1 m/s was provided in a wind tunnel. Key results and conclusions When MC < 35%, ignition is always achieved, regardless of wind velocity. However, if MC is between 35 and 85%, an external wind (increasing with peat moisture) is required to increase the reaction rate of the firebrand and thus heating to the peat sample. Further increasing the MC to be higher than 85%, no ignition could be achieved by a single laboratory firebrand. Finally, derived from the experimental results, a 90% ignition probability curve was produced by a logistic regression model. Implications This work indicates the importance of maintaining a high moisture content of peat to prevent ignition by firebrands and helps us better understand the progression of large peat fires.

Hot surface ignition of H2-air and CH4– H2-air mixtures for various equivalence ratios and heating Rates

Gaseous mixtures ignite when they come in contact with a surface with the ignition threshold temperature of the mixture. The hot surface ignition of fuels like hydrogen poses a safety threat due to its wide flammability range and high diffusivity. The present study numerically investigates hot surface ignition of H2-air and CH4/H2/air mixtures using detailed chemistry. The effects of the equivalence ratio (φ), composition and heating rate on the ignition threshold temperature of the mixture are studied. At rich mixture conditions, the ignition occurs at the side of the heated surface (glow plug). On the other hand, the lean mixtures ignite at the top of the heated surface. The variations in heating rates significantly affect the ignition temperature of rich mixtures. In contrast, the ignition temperature of the lean mixture does not show any considerable deviation concerning the variation in heating rates. The phenomenon of puffing flame is observed at lean extinction limits of H2-air mixtures. Lower ignition thresholds are observed in CH4/H2/air mixtures with high concentrations of H2. Mixtures having higher CH4 concentrations show higher ignition thresholds. The role of local equivalence ratio and heat release rate on the ignition characteristics has been studied to predict the behaviour of ignition kernel at various mixture conditions.

Ignition thresholds and initiation of pyrolysis from high flux exposures

Ignitions of solid materials from very high heat fluxes (>200 kW/m2) are differentiated from more common lower flux ignition because the required total energy input can be lower, and the process is much faster. Prior work has characterized ignition thresholds via thermal properties of the solids, flux, and fluence. The historical data, however, neglect to provide similar focus on the initiation of pyrolysis. The initiation of pyrolysis is of key relevancy because it represents an absolute threshold below which ignition is of zero probability. It is also a metric of potentially higher reliability for assessing material response because surface material properties such as absorptivity, conductivity, and density tend to change upon initial pyrolysis due to charring or other transformations. Recent data from concentrated solar flux for a variety of materials and exposures are analyzed here to explore the nature of trends and thresholds for onset of pyrolysis at high heat flux. This work evaluates initiation threshold data and provides a theoretical technique for further model development. The technique appears to be functionally appropriate to evaluate trends to aid in predicting material response to high flux exposures.

EFFECT OF COAL PARTICLE SIZE DISTRIBUTION ON LASER IGNITION CHARACTERISTICS

The ignition of hard coal grades DG, G, Zh, and K under the action of laser pulses (1064 nm, 120 μs, 1.3 J) was studied for the fractions of microparticles with a narrow size distribution in the range of 0.25-44 μm. The kinetic characteristics of the glow of samples from the entire size range were measured for each coal rank. Three stages of ignition are distinguished for each fraction. The duration of the first stage coincides with the duration of the laser pulse. The duration of the second takes a time interval of 10-15 ms (DG, G and Zh coal ranks) and 3-5 ms (K coal rank). The duration of the third stage is 60-80 ms (DG, G, and G coals) and 20 ms (K coal rank). It has been established that the threshold ignition energy densities (ignition thresholds) at all three stages depend non-monotonically on coal particle sizes. The minimum values of ignition thresholds at all three stages are achieved at particle sizes equal to 2.2 (for DG rank coal), 4.0 (for G rank coal), 0.7 (for Zh rank coal) and 2.0 μm (for K rank coal). Using the results of the proximate analysis of coals, the observed dependences of critical energy densities on the size of coal particles are interpreted.

Porous nanosheets of TKX-50 by ice-templating strategy with excellent thermal decomposition and combustion properties

ABSTRACT Nanostructured energetic materials have attracted considerable research interests during the past decades because of their improved performances in thermal decomposition and combustion. In this work, a porous nanosheet structure of dihydroxylammonium 5, 5′-bistetrazole-1, 1′-diolate (TKX-50) has been fabricated by a facile ice templating strategy, which is based on the self-assembly of TKX-50 during rapid recrystallization. Thermal decomposition properties were determined by differential scanning calorimetry/thermogravimetry (DSC/TG) and TG-FTIR analyses. The laser-ignited and constant-volume combustions and mechanical sensitivity were conducted. As-prepared TKX-50 mainly presents porous nanosheets (NS-TKX-50) assembled by the secondary nanoparticles. NS-TKX-50 is typical of mesoporous materials with high specific surface area and pore volume. Compared with raw material, NS-TKX-50 exhibits lower thermal decomposition peak temperature and higher active energy. In thermal decomposition process, a great deal of gaseous products have been generated in a very narrow temperature range. These thermal decomposition features suggest a quick energy-release rate and high energy output. Contrary to incomplete combustion of raw material, NS-TKX-50 shows high-efficiency and self-sustaining laser-ignited combustion feature with a drastically decreased ignition threshold. And its pressurization rate and peak pressure are remarkably increased. Sensitivity results confirmed the visibly reduced impact and friction sensitivity of NS-TKX-50.

Simulated impact of fill tube geometry on recent high-yield implosions at the National Ignition Facility

Inertial confinement fusion capsules fielded at the National Ignition Facility are filled with deuterium and tritium fuel by means of a fill tube. The fill tube introduces a low-density pathway into the fuel region of the capsule that allows high Z contaminant to invade the hot spot during the course of the implosion. A recent series of nominally identical high-yield implosions on the NIF has exhibited significant variability in performance. We evaluate the impact of the fill tube in these implosions computationally to determine whether variations in fill tube geometry could have contributed to this variability. The main contrast between the fill tube geometry in the six shots was the outer diameter of the capsule bore hole, a conical hole into which the fill tube is inserted. In our simulations, the geometry of the bore hole can play a significant role in the development of nonlinear flows seeded by the fill tube. We find that the amount of space between the bore hole and the fill tube is the primary factor that determines the amount of contaminant jetted into the hot spot by the fill tube and, in turn, the level of yield reduction due to the fill tube in our simulations. As a consequence, some capsules with 5 μm fill tubes are predicted to outperform capsules with 2 μm fill tubes. We also find that micrometer-scale changes to bore hole size can impact fusion yields by up to four times near the ignition threshold. Nevertheless, simulation trends do not reproduce experimental yield trends, suggesting that the fill tube geometry was not the primary factor contributing to the observed variability in performance and that the fill tube could be masking sensitivity to other asymmetries such as other micrometer-scale capsule defects like voids that were not included in our simulations.

Bridging the gap between intermediate and massive stars II: Mmas for the most metal-rich stars and implications for Fe CCSNe rates

ABSTRACT The minimum initial mass required for a star to explode as an Fe core collapse supernova, typically denoted Mmas, is an important quantity in stellar evolution because it defines the border between intermediate mass and massive stellar evolutionary paths. The precise value of Mmas carries implications for models of galactic chemical evolution and the calculation of star formation rates. Despite the fact that stars with super-solar metallicities are commonplace within spiral and some giant elliptical galaxies, there are currently no studies of this mass threshold in super metal-rich models with Z > 0.05. Here, we study the minimum mass necessary for a star to undergo an Fe core collapse supernova when its initial metal content falls in the range 2.5 × 10−3 ≤ Z ≤ 0.10. Although an increase in initial Z corresponds to an increase in the Fe ignition threshold for Z ≈ 1 × 10−3 to Z ≈ 0.04, we find that there is a steady reversal in trend that occurs for Z > 0.05. Our super metal-rich models thus undergo Fe core collapse at lower initial masses than those required at solar metallicity. Our results indicate that metallicity-dependent curves extending to Z = 0.10 for the minimum Fe ignition mass should be utilized in galactic chemical evolution simulations to accurately model supernovae rates as a function of metallicity, particularly for simulations of metal-rich spiral and elliptical galaxies.

Optical Emission Spectroscopy of Cadmium Dominated Discharges Applied for Assessment of Explosion Protection

An assessment for the safe use of electrical equipment in explosive atmospheres can be performed with the aid of a spark test apparatus. Therefore, an anodic tungsten wire with 200 µm diameter is moved along the surface of a rotating cadmium disc (cathode). The explosion chamber enclosing the electrodes is filled with a highly explosive mixture of hydrogen and air. Depending on surface topology and relative movement of the contact pair, discharges occur randomly. A model contact device is used to investigate the plasma properties and the discharge characteristics near the thermo-chemical ignition threshold of the explosive atmosphere that typically occur at voltages around 30V and currents around 30mA.Spectroscopic investigations reveal that the emission of the discharges is dominated by atomic lines of cadmium, which allow the determination of distribution temperatures.

Critical ignition conditions for propane/air premixtures impinging on electric heated surfaces: An experimental study

To contribute to exact predictions of the ignition of flammable mixture by a hot surface and ensure safety against fire, this study aims to clarify the critical ignition condition of a propane/air premixture impinging on a hot surface with external heating. The ignition threshold of heat flux depends on the flow velocity, but that of temperature hardly depends on flow velocity and equivalence ratio. The ignition occurred at the position where the residence time of species was the longest. It corresponds to the position of the lowest heat transfer coefficient. The temperature boundary layer thickness played a significant role in the ignition process as only the heat flux from the top, bottom, and back surfaces of the heater contributed to ignition in the presence of forced convection. The prediction model of the ignition threshold of heat flux and temperature was derived through dimensional analysis. This model effectively explains the ignition characteristics, regardless of the differences in thermal convection mode, dimensions, and geometric arrangements of a heater, as confirmed by comparison with reference data. Additionally, the ignition threshold of temperature can be predicted if the external heating power is known, and it is useful to assess the fire risk.

Electrophoretic assembly of Al/CuBi2O4 based-energetic films and the effect of destructive behavior with fuel/oxidant ratio

Physical destruction of microchips for data security based on thermite cannot simultaneously fulfill the demands of energy release and pressure output. Here, we have successfully assembled microchips based on Al/bimetallic oxide (CuBi2O4) energetic films through electrophoretic deposition. Al/CuBi2O4exhibits excellent energy release and pressure output, the heat release of Al/CuBi2O4is more concentrated,as extensive heat released by Al/CuO triggered the reaction of Al and Bi2O3, which will be conducive to the destructive behavior. The effects of fuel and oxide with different ratios on exothermic performance were systematically investigated, including heat release, ignition threshold energy, ignition mass loss rate and pressure release. The best fuel/oxide ratio on Al/CuBi2O4 energetic films is found to be 5.06:1 through inductively coupled plasma atomic emission spectrometry. The distribution between Al fuel and CuBi2O4rods is the most uniform at this ratio, hence it possesses the maximum heat release (926.4 J/g), lower ignition threshold (0.25 mJ), and faster pressurization rate (179.80 MPa/s). Importantly, high-speed photography results show that the intense reaction destroyed the energetic microchip (the thickness is about 0.3 mm) in only 10 ms.