PBX造型粉粒径及压制状况对撞击感度的影响

Influence of PBXs Particle Sizes and Molding Conditions on Their Impact Sensitivity Properties

为研究PBX造型粉颗粒粒径以及压制成型对撞击感度的影响规律,选用10-20μm的HMX、FOX-7、HNS-IV、LLM-105四种含能晶体与氟聚物制成PBX造型粉,测试了五种PBX颗粒粒径范围的样品经过压制前后的撞击感度,同时考察了添加石墨降感剂对撞击感度性质的影响规律。使用扫描电镜观察了不同PBX颗粒粒径中含能晶体颗粒的分布情况。结果表明,相同配方的PBX样品在不同的颗粒粒径下撞击感度结果差异明显,表现为颗粒粒径增加,撞击感度降低;而压制成型的样品撞击感度更低。添加石墨样品的撞击感度降低明显,撞击感度变化规律与未添加石墨的样品相同。由于撞击感度测试结果与PBX粉末颗粒堆积以及压制状态密切相关,在进行材料性能评估时,应选择与实际应用状态相近的样品进行撞击感度测试,从而增加结果对比的可靠程度。

In order to investigate the influence of PBXs particle sizes and molding conditions on their impact sensitivities,four energetic crystals including HMX、FOX-7、HNS-IV、LLM-105 with uniform diameter 10-20μm were fabricated as PBXs powders,and fluoropolymer was adopted as binders.The PBXs powders were sieved to five particle ranges (0.2-0.5 mm,0.5-0.8 mm,0.8-1.0 mm,1.0-1.25 mm,and 1.25-1.6 mm),and their impact sensitivities were measured and compared.Graphite as desensitivity additives was also studied.SEM was used to observe energetic crystal distribution in different PBXs powders.The results indicated that with the increase of PBXs particle sizes,the impact sensitivity decreased;and the PBXs samples after mold pressing presented the lowest impact sensitivity.Graphite as additives further decreased the impact sensitivity of PBX samples,and the influence of these graphite-added PBXs samples had the same variation trend with those without graphite.There are obvious relationship between PBXs particle sizes,molding conditions and impact sensitivities values,therefore,the evaluation of impact sensitivity performances of energetic materials should adopt the testing results with similar physical conditions,in order to increase the comparison reliability.