【作者】 吴旭；

【导师】 应三九；

【作者基本信息】 南京理工大学 ， 材料工程（专业学位）， 2017， 硕士

【摘要】 本文以高固含量发泡复合材料为研究对象,采用超临界CO₂分步升温的间歇法发泡工艺,以太根药和B胶为基体填充大量RDX并以PMMA为辅助发泡体,进行了微孔可燃器件成型及发泡工艺的探索,研究了发泡工艺条件对其溶解性能以及微孔结构的影响;并采用受限发泡模具对此材料进行受限发泡,制备了微孔复合材料的力学样条,研究了不同发泡条件对其力学性能的影响。结果表明,CO₂在高固含量复合材料中的溶解量随饱和时间的增加先快速增加然后趋于平衡;溶解量随着饱和温度的上升而降低却随着饱和压力的升高而升高;受限条件和样品厚度对溶解量没有明显的影响;增加溶解量可明显提高高固含量复合材料的解吸附系数。研究发现增加发泡温度与发泡时间可以增加泡孔直径降低泡孔密度;增加饱和压力以及受限条件可以减小泡孔直径并使泡孔更为致密;饱和时间在6-12小时之间进行发泡,泡孔会随着饱和时间增加而变大;饱和温度对泡孔参数的影响不明显且快速卸压法制备的高固含量微孔含能材料泡孔密度不如分步升温法高。超临界发泡处理会导致材料的拉伸强度降低以及断裂伸长率的提高;增加弹性体用量以及饱和压力可以提高材料的抗冲击强度;增加发泡温度、发泡时间以及平衡前增大饱和时间均会带来冲击强度的降低;饱和温度对材料冲击性能的影响不明显。最后,针对某口径火炮装药,本课题利用现有配方进行了可燃器件模压成型,解决了薄壁长筒状器件成型困难的问题;另外,采用超临界CO₂发泡技术对可燃器件进行燃速调节,为轻质高能弹药研究打下了实验基础。更多还原

【Abstract】 In this study,we mainly do researches about high solid content foamed composites.The effects of foaming process parameters such as saturation time,temperature and pressure on microcellular structure and mechanical properties of microcellular combustible components have been studied.In this paper,we took TEGDN propellant and B glue as the matrix which filled with massive content of RDX and we also took PMMA as auxiliary foaming agent.Two steps intermittent foaming process of supercritical CO₂ was used to study the influence of foaming process conditions to its solubility and cell structure.We also used constrained foaming molds to produce constrained foaming mechanical spline to study the effects of various foaming conditions on its mechanical properties.The results show that the solubility of supercritical carbon dioxide in high solid content composites increased with the rising of saturation pressure and time.But the solubility decreased with the rising of saturation pressure while constrained conditions and sample thicknesses have little effect on it.The increasing of solubility can significantly increase the desorption diffusivities of CO₂ in high solid content composites.The microcellular structure of high solid content foamed energetic composites can be affected by the foaming process.It was found that increasing the foaming temperature and time can increase the cell diameter and decrease the cell density.While limited conditions and increase the saturation pressure can reduce the cell diameter and make the cell denser.Within 6 to 12h,the extending of saturation time will make the cell bigger.The effect of saturation temperature on the cell parameters is not clear and the densification of high solid content foamed energetic composites prepared by rapid depressurization method is not as good as stepwise heating method.With the treatment of supercritical CO₂ foaming,the tensile strength of high solid content foamed composites decreased but the elongation at break of it increased.The impact strength of our composites increased with the increasing of elastomer and saturation pressure.And with the increasing of foaming temperature,foaming time and the saturation time before equilibration,the impact strength of our composites decreased.The effects of saturation temperature on impact strength of our composites is not clear.At last,we studied the filling and molding of high solid content foamed composites and problems of forming thin-walled cylindrical devices were solved.In addition,supercritical CO₂ foaming method can be used to change the burning rate of combustible devices which laid the experimental foundation for the researches of lightweight and high-energy ammunition.更多还原