铝粉超细化对KClO3/Al/S配方药剂特性的影响

为研究铝粉超细化后对烟火药剂性能的影响,将普通铝粉和纳米铝粉分别与氯酸钾、硫黄粉按照零氧平衡的同一配比(17%Al+63%KClO3+20%S)配制成烟火药剂,分别用0#样品和1#样品表示。用ARC、WL-1型落锤仪和MGY-1型摆式摩擦感度仪等试验装置从热安全性、撞击感度和摩擦感度等方面进行对比试验。结果表明,与含普通铝粉的0#样品相比,含纳米铝粉的1#烟火药剂热分解的初始反应温度明显降低(118.67℃<123.3℃),反应到达最大温升速率所需的时间明显延长(4.94min>0.13 min),反应所能达到的最高压力明显降低(2.77 MPa/g<3.14 MPa/g),反应动力学因子明显降低(361.85 kJ/mol<409.41 kJ/mol),撞击感度明显下降(12%<100%)。这说明铝粉粒径对药剂的性能有一定的影响。纳米铝粉的加入在加速烟火药剂反应进程的同时,可有效降低其反应的激烈程度、压力危险性和撞击危险性,即铝粉超细化后可以有效改善烟火药剂的性能,提高其安全性。

Effects of ultrafine-aluminum on the properties of KClO3/Al/S pyrotechnics

To study the effects of ultrafine aluminum powder on pyrotechnics properties,thermal safety and mechanical sensitivity tests were carried out by some test devices such as accelerating rate calorimeter(ARC),WL1type falling-hammer instrument and MGY-1type swing friction sensitivity instrument.The tests were conducted on mixture of same amount of aluminium powder with two types of pyrotechnics in accordance with zero oxygen balance composition: 63% KClO3 + 17%Al + 20%S.Sample mixture containing common aluminum powder(the particle size is about 7 500 nm) was marked as 0# while sample mixture containing nano-aluminum powder(the particle size is about 50 nm) was marked as 1#.It was found that compared with sample 0#,the sample 1#can effectively reduce the initial reaction temperature of pyrotechnics(118.67 ℃<123.3 ℃),extend the time required to reach maximum reaction temperature rising rate(4.94 min>0.13 min),reduce the highest achievable pressure in the thermal decomposition reaction(2.77 MPa/g<3.14 MPa/g),significantly reduce the kinetic factor(361.85 kJ/mol<409.41 kJ/mol) and decrease the impact sensitivity(12%<100%).Theseresults showed that the particle size of aluminum powder has some certain impacts on the performance of pyrotechnics.The addition of nano-aluminum powder in KClO3/Al/S pyrotechnics can effectively accelerate the reaction speed and reaction process of pyrotechnics as well as reduce its reaction intensity,pressure risk and crash risk.