PYROSTATIC TESTS OF JA-2 TYPE POWDER

Literature data concerning ballistic properties of JA-2 powders was studied. The data was compared with results of own tests received for powder LO5460 manufactured by Nitrochemie AG. Pyrostatic tests were carried out in the manometric chamber having the volume of 200 cm3. The force of the powder and the co-volume of powder gases were measured. The influence of thermal losses into these parameters was evaluated by using a methodology proposed by the authors. Exponent value in the powder burning law and curves of dynamical liveliness of the powder were established. The curves actually overlap what shows the adequacy of the physical law of burning. It was proved that the ignition of tested powder takes place prior the complete burning of an igniting charge. It was taken into account at modification of the method for establishing the dynamic liveliness. Exploiting results of measurements for powder grains geometry and the curves of dynamical liveliness a coefficient of linear burning velocity was established. A good compliance with literature data was achieved for the dependence of linear burning rate on the pressure. It was proved that the geometrical burning law is adequate with the description of tested powder burning for changes of relative volume of burned powder above 0.2.

Influences of Firing Process System on Foam Glass Properties

Waste glass and polishing waste residue as raw materials were used to make foamed glass. The preparation of firing technology was optimized and the powder burning method was used, by which the foam glass possess good performance, such as light weight, high strength, low thermal conductivity. Results show that sintering temperature and foaming temperature influence the specific strength of foam glass greatly, and the optimal preparation process of foam glass was confirmed: sintering temperature is 1050°C, foaming temperature is 870°C minutes, foaming time is 35min.