SiC纤维表面CVD SiC涂层对其单丝强度的影响

采用化学气相沉积(CVD, Chemical Vapor Deposition)工艺在KD-I型SiC纤维表面制备了SiC涂层,选择2h、4h、6h和8h四个时间点研究了沉积时间对纤维性能的影响.结果表明:具有CVD SiC涂层的SiC纤维较无涂层的纤维来说强度有所下降;在所研究的沉积时间范围内,随着沉积时间的增加,涂层的厚度有所增加,涂层由不连续的岛状转变为连续层状,纤维的单丝强度出现了先升后降的趋势.     

自蔓延反应喷涂表面涂层技术进展

围绕自蔓延反应喷涂技术与工艺研究和自蔓延反应喷涂相关理论研究两个方面,介绍了这一技术领域的发展状况。SHS反应喷涂技术将燃烧合成与传统热喷涂相融合,将各类高化学能的反应型粉材、线材引入喷涂技术中制备高性能陶瓷和金属间化合物涂层,发展了SHS反应药芯线材电弧喷涂、SHS等离子喷涂、爆炸反应喷涂以及SHS反应火焰喷涂等技术手段。一方面,对其中的配系设计、控制参数、涂层性能和相关设备等方面开展了深入的实验研究;另一方面,围绕涂层形成过程、喷涂条件下的反应机理与模式,以及反应喷涂过程中的能量状态和粒子的物理状态等方面开展了初步的理论研究,正在构筑较完整的理论体系。     

华东烧结模型的数学计算(Ⅱ)

通过热力学分析和数学计算,讨论颗粒呈现面心立方堆积方式时,华东烧结模型中膨胀机制和收缩机制对烧结体总表面能的作用和总孔隙度比变化的影响,计算表明烧结过程中收缩机制占主导地位。     

铁红环氧酯涂层中缓蚀剂的研究

在有机涂层中加入缓蚀剂构成耐蚀涂层,可以进一步提高原涂层的耐蚀能力。本文研究了一种缓蚀剂HN(由H和N复配而成,H为杂环类,N为胺类),用在普通涂层—铁红环氧酯中试验。采用了四种方法:电化学交流阻抗法,盐雾箱试验法,人造海水浸泡,海上实船挂片,并分别与未加缓蚀剂的原涂层进行对比,对各涂层的耐蚀性能进行评定。结果表明:在铁红环氧酯中加入少量HN缓蚀剂后,在不改变原涂层附着力的情况下,明显提高了原涂层的耐蚀能力。     

聚氨酯防腐涂料综述

介绍了聚氨酯防腐涂料的种类、成分及其性能,并与现有的防腐涂料进行了比较。     

活性粉末混凝土200（RPC200）的配制试验研究

进行了活性粉末混凝土(RPC)的配制试验,通过5批试件分别探讨砂灰比、石英粉、硅灰、水胶比和钢纤维等因素单值变化时对RPC流动度以及抗折强度、抗压强度的影响.研究表明:在常规制作工艺条件下,配制出抗压强度和抗折强度分别为145.6 MPa和26.68MPa的无纤维RPC;当钢纤维含量为6%时,RPC的抗压强度和抗折强度分别达到了201.3MPa和73.67 MPa.     

碳化硼涂覆的碳纤维的抗热氧化性研究

用自己合成的裂解能得到碳化硼的聚碳硼烷,对碳纤维进行涂层,并详细测试了涂层碳纤维的抗热氧化性能。     

A quasi-isentropic model of a cylinder driven by aluminized explosives based on characteristic line analysis

A quasi-isentropic study on the process of driving a cylinder with aluminized explosives was carried out to examine the influence of the aluminum (Al) reaction rate on cylinder expansion and the physical parameters of the detonation products. Based on the proposed quasi-isentropic hypothesis and relevant isentropic theories, the characteristic lines of aluminized explosives driving a cylinder were analyzed, and a quasi-isentropic model was established. This model includes the variation of the cylinder wall velocity and the physical parameters of the detonation products with the Al reaction degree. Using previously reported experimental results, the quasi-isentropic model was verified to be applicative and accurate. This model was used to calculate the physical parameters for cylinder experiments with aluminized cyclotrimethylenetrinitramine explosives with 15.0 % and 30.0 % Al content. The results show that this quasi-isentropic model can be used not only to calculate the cylinder expansion rule or Al reaction degree, but also to calculate the physical parameters of the detonation products in the process of cylinder expansion. For explosives with 15.0 % and 30.0 % Al, 24.3 % and 18.5 % of the Al was found to have reacted at 33.9 μs and 34.0 μs, respectively. The difference in Al content results in different reaction intensity, occurrence time, and duration of two forms of reaction (diffusion and kinetic) between the Al powder and the detonation products; the post-detonation burning reaction between the Al powder and the detonation products prolongs the positive pressure action time, resulting in a continuous rise in temperature after detonation.     

Preparation and characterization of HMX/NH2-GO composite with enhanced thermal safety and desensitization

To improve the safety of HMX, HMX/NH₂-GO composite was prepared with aqueous ammonia functionalized graphene oxide (NH₂-GO). The composite was characterized by SEM, Zeta potential, XPS, Raman spectrum, XRD, HPLC, DSC and BAM sensitivity test. The results indicated that the functionalization with aqueous ammonia can enhance the interaction between GO and HMX, and more efficiently desensitize the explosive. The optimal impact sensitivity of the HMX/NH₂-GO composite can be not less than 40 J, which is also the most insensitivity compared to the previous reports prepared by coating desensitization with non-energetic desensitized material. Moreover, the potential reason for the different impact and friction sensitivity was also discussed, which may bring a novel perspective to achieve the desensitization of energetic material.     

火炮发射药装药自动识别方法

发射装药号是影响火炮身管寿命的重要因素,为自动识别火炮发射药的装药号,避免人工记录失误和完善火炮射弹履历,分析了装药号自动识别原理,运用火炮动力学分析理论和ADAMS虚拟样机技术,建立火炮发射动力学虚拟样机.通过仿真试验获取样本数据,应用BP神经网络进行学习和训练,从而建立装药号和测试数据之间的非线性映射关系,实现对火炮发射装药号的精确预测.