The stability of pyrotechnic composition used in flame detonator was studied at severe temperatures （-70-130 ℃） for 5 d. For single N-LTNR（normal lead styphnate）, camera was used to observe the shape and colour o...The stability of pyrotechnic composition used in flame detonator was studied at severe temperatures （-70-130 ℃） for 5 d. For single N-LTNR（normal lead styphnate）, camera was used to observe the shape and colour of N-LTNR in the DSC（differential scanning calorimetry） furnace during continuous heating and cooling processes. Based on the DSC-TGA（thermogravimetric analysis） results, it can be seen that when the temperature exceeded 110 ℃, N-LTNR lost its crystal water, making the energetic material become darker in colour, smaller in dimension, lager in volume and lighter in weight（3.416%）; when the temperature was below -40 ℃, the phenomenon of sample broking, jumping and cracking happened. For the N-LTNR and Pb（N3）2（lead azide） double layers, the loss of N-LTNR＇s crystal water at the temperature higher than 110 ℃ caused the hydrolysis reaction of Pb（N3）2, and the purity of Pb（N3）2 measured after the temperature cycling decreased from 98.6% to 95.26%. For the flame detonator, the height and diameter of the flame detonator were measured and no apparent changes of them were found. The p-t（pressure-time） test shows that the peak pressure was decreased by 3.9%. Therefore, the operating temperature of this flame detonator should be limited to -40-110 ℃.展开更多
基金Supported by the National Natural Science Foundation of China（No. 11172042）.
文摘The stability of pyrotechnic composition used in flame detonator was studied at severe temperatures （-70-130 ℃） for 5 d. For single N-LTNR（normal lead styphnate）, camera was used to observe the shape and colour of N-LTNR in the DSC（differential scanning calorimetry） furnace during continuous heating and cooling processes. Based on the DSC-TGA（thermogravimetric analysis） results, it can be seen that when the temperature exceeded 110 ℃, N-LTNR lost its crystal water, making the energetic material become darker in colour, smaller in dimension, lager in volume and lighter in weight（3.416%）; when the temperature was below -40 ℃, the phenomenon of sample broking, jumping and cracking happened. For the N-LTNR and Pb（N3）2（lead azide） double layers, the loss of N-LTNR＇s crystal water at the temperature higher than 110 ℃ caused the hydrolysis reaction of Pb（N3）2, and the purity of Pb（N3）2 measured after the temperature cycling decreased from 98.6% to 95.26%. For the flame detonator, the height and diameter of the flame detonator were measured and no apparent changes of them were found. The p-t（pressure-time） test shows that the peak pressure was decreased by 3.9%. Therefore, the operating temperature of this flame detonator should be limited to -40-110 ℃.
