Papers by Keyword: Combustion Products

Abstract: The intermediate and final combustion products of pressed aluminum nanopowder are studied. It is found that the main combustion product is aluminum nitride. In the intermediate stages of combustion, aluminum oxide (γ-Al₂O₃) and oxynitride (Al₅O₆N) are the first to form on the sample surface, and aluminum nitride is formed next. The use of sliding (incident at a small angle to the surface) synchrotron radiation made it possible to determine with high accuracy (in time) the sequence of stages of formation of crystalline products during combustion of the aluminum nanopowder.

Abstract: In the presented paper is assessed fire risk of pellets made from spruce wood (Picea abies L.) without bark, processed by hot pressing without the use of additional chemicals. Fire risk was assessed on the basis of heat release rate (HRR), the specific carbon monoxide production rate (SCPR) and the time dependence of the induction period of spontaneous ignition on temperature. HRR and SPCR were determined on the cone calorimeter test performed according to ISO 5660-1:2002 standard. Samples were loaded by 20 kW/m² heat flux during the test. The maximum HRR was 229 kW/m² and average HRR was 55 kW/m². Maximum SCPR was 0.37 g/(m²s) and the average SCPR was 0.16 g/(m²s). The dependence of the induction period of spontaneous ignition on temperature was determined by a modified test performed according to ISO 871:2006 standard. Modification of the test procedure was based on measurement of the induction time period of the spontaneous ignition on temperature, and temperatures higher of 20, 40, 60, 80 and 100 °C than spontaneous ignition temperature. The obtained data proved an exponential dependence of the induction period of spontaneous ignition on temperature.

Abstract: Chemical activity parameters for aluminum nanopowder in mixtures with zinc, graphite, silicon, iron and copper powders are explored. The study of the phase content of combustion products shows that these mixtures can be used to produce precursors for ceramic materials.

Abstract: Possibility of getting the boron-containing composite materials at aluminum-thermal combustion of boron-containing systems in argon medium. The combustion took place in reactor (at up to 30 atm. argon pressure). Influence of argon pressure and aluminum content (in initial feed) on content of the solid (titanium diboride and aluminum oxide) phases in synthesis products.

Abstract: The results of a new potentiometric technique for in situ diagnostics of self-propagating high-temperature synthesis (SHS) of different complex oxides are presented. This technique is based on electrochemical processes. The characteristic peaks attributed to the electric responses from cation streams of alkali, alkaline-earth and some elements of group VI are discovered and the respective routes of the corresponding chemical reactions found.