NG/NC基体对复合改性双基推进剂机械感度的影响

目的 研究硝化甘油(NG)增塑的硝化棉(NC)基体对复合改性双基(AP/CMDB)固体推进剂机械感度的影响。方法 采用光辊压延法和柱塞式挤出法,分别制备NG增塑的NC吸收药样品及以其为基体的固体推进剂样品,采用扫描电镜表征不同增塑比的NC/NG基体及推进剂的微观形貌,采用摩擦感度仪、撞击感度仪测试NG/NC基体及推进剂的机械感度。结果 当NG的质量分数由41.5%降至37.5%时,NG/NC基体的撞击感度降低53.0%。加入超细高氯酸铵(AP)后,采用NG质量分数为37.5%的基体的推进剂,撞击感度增加46.7%,而加入球形铝粉后,AP颗粒分散均匀性和NG/NC网络均匀性增加,推进剂抗冲强度提高,撞击感度及摩擦感度分别降低44.4%和20.0%。结论 AP/CMDB推进剂的机械感度与微观结构明显相关,AP的加入提高了推进剂机械感度,Al粉的加入提高了粉体的分散均匀性和NG/NC对粉体颗粒的包裹效果,降低了推进剂机械感度。

Effect of NG/NC Matrix on the Mechanical Sensitivity of AP/CMDB Propellant

The paper aims to study the effect of nitrocellulose matrix plasticized by nitroglycerin on the mechanical sensitivity of AP/CMDB propellant. The NG/NC matrix and AP/CMDB propellant samples were respectively prepared by roll calender and plunger extruder. Impact sensitivity and friction sensitivity of them were tested. Impact sensitivity of NG/NC matrix decreased 53% when NG mass fraction was reduced to 37.5% from 41.5%, but increased 46.9% when superfine AP was added in. Spherical Al powder was added in after, the uniformity of AP dispersion and NG/NC bond evidently increased, impact intensity of the AP/CMDB propellant also increased, impact sensitivity and friction sensitivity respectively decreased 44.4% and 20.0%. The mechanical sensitivity AP/CMDB propellant has apparently relations with its microstructure, it is raised up by adding into superfine AP powder as the agglomeration of AP and depressed down by adding spherical Al powder as the modification of dispersion uniformity of AP and Al particles.