Catalytic action of nano Bi₂WO₆ on thermal decompositions of AP, RDX, HMX and combustion of NG/NC propellant

Abstract

Nano Bi 2 WO 6 was prepared by hydrothermal method and characterized by XRD, SEM and EDS. Catalytic decomposition effects of nano-Bi 2 WO 6 on AP, RDX and HMX were studied by DSC method. Nano Bi 2 WO 6 can reduce the decomposition temperature and apparent activation energy of decomposition process. The thermal behaviors of Bi 2 WO 6 -DB propellant were studied. The self-accelerating decomposition temperature and critical temperature of thermal explosion are 168.3 and 178.1 C, respectively. Nano Bi 2 WO 6 used as burning catalyst of NG/NC propellant can greatly increase the burning rate, decrease the pressure exponent and form specific high-pressure "platform" at 16-22 MPa.Nano Bi 2 WO 6 exhibits good application performance in solid propellant.

Study on Comparative Performance of CL‐20/RDX‐based CMDB Propellants

“…The effects of CL-20 and RDX on basic properties of CMDB propellants were investigated, the major findings could be summarized as follows: 1) The calculations on energetic properties for CL-20/RDX-CMDB propellants showed that energetic properties of propellant with CL-20 were superior to of propellant with RDX. 2) The data on burning rate revealed that with the increase of RDX/CL-20 mass fraction in the propellants, the burning rates at low pressure (2-8 MPa) remained almost the same but differ observably at high pressure (10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22). With the increase of CL-20 mass fraction in the propellants, the burning rates of propellants could be enhanced significantly, but the burning rates of propellants containing RDX decreased.…”

“…Hexanitro hexaazaisowurtzitane (HNIW or CL-20) is superior to hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and cyclo-tetra-methylenetetranitramine (HMX) with respect to density, enthalpy of formation, and oxygen balance [6][7][8][9]. CL-20 has evoked interest as a promising candidate, replacing various energetic compounds such as RDX, HMX and ammonium perchlorate (AP), for realizing the eco-friendly, high-performance, highspecific impulse(Isp), minimum signature propellants for futuristic missiles and space missions [10][11][12][13][14].…”

Study on Thermal Behaviour of AP/LiBH4 Energetic System

“…1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 3 Results and Discussions 3.1 Thermal Behaviour of AP/LiBH 4 Powder Figure 3 shows the temperature-time and heat-time curves of three heated energetic samples. According to the literature [24], AP commences an exothermic decomposition at more than 230 8C generally. As Figure 3(a) shows, no significant heat release is observed below 100 8C for AP.…”

Unravelling the Effect of Anthraquinone Metal Salts as Wide-range Plateau Catalysts to Enhance the Combustion Properties of Solid Propellants

“…It is also well known that by using nano-PbDHB, nano-PbAB and nano-PbP, the plateau region is extended to 4-12 MPa [39,40], while it is difficult to decrease the n value above 12 MPa. K. Z. Xu et al [33] found that the use of nano-Bi 2 WO 6 , can improve n in the high pressure region, but the catalytic efficiency was only up to 1.5. Some energetic combustion catalysts, including 4-amino-3,5-dinitropyrazole lead [28] and 3-nitrophthalate lead [40], also generate plateau combustion below 10 MPa.…”

“…In comparison, some energetic catalysts such as 3-nitro-1,2,4-triazol-5-one (NTO) [24][25][26], 4-(2,4,6-trinitroanilino)benzoic acid (TABA) [27] and 4-amino-3,5-dinitropyrazole (DNP) [28][29][30] metal salts, do not show a significant reduction in the pressure exponent of solid propellants, and some of them are very dangerous and require a high standard of precautions/protocols for their manufacture. Many research groups have also focused on the preparation of nano-sized catalysts, including nano-Fe 2 O 3 [31], CuO [32], Bi 2 WO 6 [33], and copper β-resorcylate [34]. Moreover, despite these compounds exhibiting great efficacy in enhancing the thermal decomposition rates of energetic materials, they are still unable to modify the combustion properties of solid propellants above 10 MPa because of the difficulties in maintaining a high degree of dispersion by limiting aggregation.…”