纳米硼粉活性的激活、保持及作用机理研究

Boron is a significant component of energetic materials and fuel.It's important to keep the activity of boron in its ignition and energy releasing. Layer oxidation of industrial boron,low activity,incomplete ernergy releasing and inactivation of high-purity boron caused by oxidation in open air exist,sevral solutions are found including high-ernergy wet milling,solvent purification,high-temperature annealing which can strip the oxidation layer of industrial boron.Next,the high-purity boron is coated with combustion catalyst in order to protect the high-purity boron from oxidation and inactivation . At last,this coated high-purity boron will be added into TEGDN/NC propellant and the changing of TEGDN/NC combustion characteristics will be investigated,then a new theory can be established in this field.The technics of high-ernergy wet milling,solvent purification,high-temperature annealing are easy,cheap and time saving and can activate the senescent boron.The combustion catalyst coating can improve the ignition performance.It can protect high-purity boron from oxidation in the open air also.At the same time,the coated boron have a dual role,it can increase the energy density of TEGDN/NC and improve the combustion performance of TEGDN/NC by reducing the pressure exponent of burning rate.

硼是重要的含能材料燃料组分,硼的活性对其点火和能量释放有重要意义。本研究针对工业硼粉表面氧化层厚、活性低、能量释放不充分而高纯硼粉常温易氧化丧失活性等问题，综合采用高能湿法球磨、溶剂提纯、高温退火的方法，对工业硼粉氧化层进行剥离，制备成高活性硼粉；为保持活性，采用燃烧催化剂对高活性硼粉进行包覆。包覆后，高活性硼粉在空气中不易氧化、活性不丧失。最后将高活性包覆硼粉应用在太根发射药中，研究硼的作用机理，为硼粉的应用提供理论依据。高能湿法球磨、溶剂提纯及高温退火相结合的硼粉活化工艺，可以实现对老化硼粉的活化，具有时间短、成本低、操作方便等优点。采用燃烧催化剂对高活性硼粉进行包覆，一方面使硼在空气中不氧化，另一方面改善硼的点火性能。在太根发射药中，包覆硼粉也具有双重作用。即可以提高推进剂的能量密度，又改善太根发射药的燃烧性能，降低燃速压力指数。

硼是重要的含能材料燃料组分,硼的活性对其点火和能量释放有重要意义。本研究针对工业硼粉表面氧化层厚、活性低、能量释放不充分而高纯硼粉常温易氧化丧失活性等问题，综合采用高能湿法球磨、溶剂提纯、高温退火的方法，对工业硼粉氧化层进行剥离，制备成高活性硼粉。单纯的湿法球磨使得硼粉氧化增重由43%降为40%，但是，球磨后最大燃速甚至比新出厂的硼粉延期药的燃速提高29%；为保持活性，采用纳米铝粉对高活性硼粉进行包覆。包覆后，高活性硼粉在空气中不易氧化、活性不丧失。氧化增重比原样硼粉提高121%，放热量提高444%，燃速比新硼粉延期药的燃速提高411%。采用静电纺丝技术支部了B/NC复合纤维，B与NC质量比为1∶5时，B/NC纤维的硼放热峰温比纯硼粉降低了34.5℃，硼增重量从89.37%（纯硼粉）增加到155.22%（B/NC纤维），常压燃速比B/NC简单物理混合物提高了79%，定容燃烧压力增加速率提高了140.39%。采用静电喷雾的方法制备了n-B/Al/PVDF微球。制得的微球颗粒直径大小分布在1-5µm。n-B/Al/PVDF微球中，不含n-Al和低含量（10wt%和30wt%）n-Al的微球都不能在试验条件下燃烧。而含50wt%和70wt% n-Al的n-B/Al/PVDF微球都能燃烧，并且燃烧剧烈并发出强烈的光，并在燃烧过程中观察到了硼在氧气中燃烧特有的绿色火焰，表明n-B在燃烧测试过程中发生了燃烧。对燃烧残渣进行XRD分析发现，残渣中有Al、Al2O3和AlB2，说明Al和B除了和氧气发生反应外，二者同样在燃烧的高温环境下发生了反应而生成AlB2。