Presented herein is a study on the ignition reaction kinetics and mechanism of B4C/KNO3 and B4C/KClO4 pyrotechnic smoke compositions using the non-isothermal thermogravimetry and differential scanning calorimetry techniques. The pyrotechnics in oxygen balance of − 10%, − 20% and − 30% were prepared for the experiments. The results of measurements showed that the pyrotechnics in oxygen balance of − 20% had the highest enthalpy. The activation energy (Ea) of ignition reactions was calculated by using Ozawa–Flynn–Wall (OFW) and Kissinger–Akahira–Sunose (KAS) methods. The Ea values of B4C/KNO3 and B4C/KClO4 were 139.5 and 214.6 kJ mol−1 calculated by OFW method, and 129.3 and 210.7 kJ mol−1 by KAS method. The differential and integral reaction mechanism functions of B4C/KNO3 and B4C/KClO4 were determined, respectively, by z(α) master plots method, f1(α) = 2(1 − α)[− ln(1 − α)]1/2, g1(α) = [− ln(1 − α)]1/2, and f2(α) = 3(1 − α)[− ln(1 − α)]2/3, g2(α) = [− ln(1 − α)]1/3. The pre-exponential factors, lnA = 11.6 and 22.3 min−1, were obtained by the intercept of KAS method for ignition reaction of B4C/KNO3 and B4C/KClO4 pyrotechnics. Based on the results, the burning rates, thermal sensitivities and application methods of B4C/KNO3 and B4C/KClO4 were predicted.
Pyrotechnics TG/DSC Ignition reaction Kinetics
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The support for this work was provided by the National Natural Science Foundation of China (Project No. 51676100).
Eaton JC, Lopinto RJ, Palmer WG. Health effects of hexachloroethane (HC) smoke; accession number ADA277838; Defense Technical Information Center (DTIC): Fort Belvoir, VA, 1994; pp 1–60.Google Scholar
Shaw AP, Poret JC, Gilbert RA, et al. Development and performance of boron carbide-based smoke compositions. Propellants Explos Pyrotech. 2013;38(5):622–8.CrossRefGoogle Scholar
Shaw AP, Diviacchi G, Black EL, et al. Versatile boron carbide-based visual obscurant compositions for smoke munitions. ACS Sustain Chem Eng. 2015;3(6):150423154904007.CrossRefGoogle Scholar
Vyazovkin S, Burnham AK, Criado JM, et al. ICTAC Kinetics Committee recommendations for performing kinetic computations on thermal analysis data. Thermochim Acta. 2011;520(1–2):1–19.CrossRefGoogle Scholar
Pouretedal HR, Loh Mousavi S. Study of the ratio of fuel to oxidant on the kinetic of ignition reaction of Mg/Ba(NO3)2 and Mg/Sr(NO3)2 pyrotechnics by non-isothermal TG/DSC technique. J Therm Anal Calorim. 2018;132:1307–15.CrossRefGoogle Scholar
Vyazovkin S. Alternative description of process kinetics. Thermochim Acta. 1992;211(1):181–7.CrossRefGoogle Scholar
Flynn JH. The ‘temperature integral’—its use and abuse. Thermochim Acta. 1997;300(1–2):83–92.CrossRefGoogle Scholar
Miyata K. Combustion of boron-pyrotechnics. In: Joint propulsion conference and exhibit. 2013.Google Scholar
El-Awad AM. Catalytic effect of some chromites on the thermal decomposition of KClO4 mechanistic and non-isothermal kinetic studies. J Therm Anal Calorim. 2000;61(1):197–208.CrossRefGoogle Scholar
Liu PJ, Liu LL, He GQ. Effect of solid oxidizers on the thermal oxidation and combustion performance of amorphous boron. J Therm Anal Calorim. 2016;124(3):1587–93.CrossRefGoogle Scholar
Ozawa T. A new method of analyzing thermogravimetric data. Bull Chem Soc Jpn. 1965;38:1881.CrossRefGoogle Scholar
Flynn JH, Wall LA. General treatment of the thermogravimetry of polymers. J Res Natl Bureau Stand Part A. 1966;70:487.CrossRefGoogle Scholar
Akahira T, Sunose T. Method of determining activation deterioration constant of electrical insulating materials. Res Rep (Chiba Inst Technol) Sci Technol. 1971;16:22–31.Google Scholar
Malek J. The applicability of Johnson–Mehl–Avrami model in the thermal analysis of the crystallization kinetics of glasses. Thermochim Acta. 1995;267:61–73.CrossRefGoogle Scholar
Brown ME. Introduction to thermal analysis. 2nd ed. Dodrecht: Kluwer; 2001.Google Scholar
Pouretedal HR, Ebadpour R. Application of Non-isothermal thermogravimetric method to interpret the decomposition kinetics of NaNO3, KNO3, and KClO4. Int J Thermophys. 2014;35(5):942–51.CrossRefGoogle Scholar