纳米铝粉和镍粉对复合推进剂燃烧性能的影响

Effect of nano aluminum and nickel powders on the combustion properties of composite propellant

对铝含量较低的AP复合推进剂燃速进行测试,外加2%的n Ni或4/1的n Al/g Al级配均可提高低压下燃速和降低燃速压强指数,改善推进剂的燃烧性能,而采用1/1的n Al/g Al级配则降低推进剂的燃烧性能。通过对推进剂样品的能量特性、火焰结构、燃烧残渣的观测以及热分析(TG和DTA实验),n Al与n Ni在燃烧中有不同于g Al的行为。具有较低的点火阈值和较短的燃烧时间,同时n Al倾向于单颗粒燃烧,有别于g Al的凝聚燃烧行为;n Ni则催化了复合推进剂中主要组分AP的热分解,多种因素共同作用促进了推进剂的燃烧。

The effect of nano metal powders on the burning rates of composite propellant was studied. The results indicate that the addition of 2% nano nickel powders (n-Ni) or the usage of grading aluminum powders with the ratio of nano aluminum (n-Al) to general aluminum (g-Al) 4:1 can effectively improve the combustion of propellant. The usage of grading aluminum powders with the ratio of n-Al to g-Al 1:1 will worsen the combustion of propellant. An interpretative mechanism for the effects of nano metal is developed on the basis of energy response, combustion residue, and flame structures of the propellant containing nano metal powders. The thermal analysis properties of the propellant and metal powders (n-Al and g-Al) are also considered. That implies the ignition threshold and combustion time from initial particle size to burnout of n-Al and n- Ni are lower compared with g-Al. Besides n-Al is inclined to burn in single and n-Ni have the greatest influence on the decomposition properties of AP among metal powders. All these factors work together and will have obvious effects on the ignition and combustion characteristics of composite propellants.