共查询到19条相似文献,搜索用时 78 毫秒
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前言武器系统要求在不损失能量的前提下降低炸药和推进剂的感度。本课题的研究目的是探讨炸药与以下性质的关系:(1)粘结剂与炸药之间的表面相互作用; (2)PBx的化学及力学性质。 相似文献
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吴元国 《现代塑料加工应用》1990,(4):42-45
一、前言经过塑料生产厂家的不断探索和开发,塑料板材在包装业、制冷业、家用电器、汽车制造业、航空业等领域的应用得到了飞速发展。随着使用途径的不断拓宽,对板材的性能提出了更高的要求,如电冰箱门衬用板材既要有良好的表面光泽又要有内在的耐低温性和优秀的抗冲击性能等、这对于单一塑料原料的板材很难适应这种多性能的要求,从而提出了对塑料板材进行复合的问题。 相似文献
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聚酰胺塑料是一种用途广泛的热塑性工程塑料。本文对目前我国已批量生产的PA6、PA66和PA1010三个较大品种的吸水性、硬度、摩擦磨耗、蠕变、拉伸、冲击、弯曲、压缩和热性能等全面的物理力学性能进行了评价试验;并和日本产的1022B PA6怍了一些对比。结果表明,综台物理力学性能PA66优于PA6,后音又优于PA10lO;国产PA6和日本产1022B则性能接近。 相似文献
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混合炸药对温度渐变环境的适应性研究 总被引:6,自引:0,他引:6
研究了几种混合炸药在经历了温度渐变试验(又称高低温循环试验)后的尺寸、质量、力学性能的变化,以及外观和内部结构的改变,分析了环境因素的影响程度及作用机理。建立了混合炸药对温度渐变环境的适应性试验方法,评价了混合炸药对温度渐变环境的适应能力。为混合炸药的配方设计、生产、运输和贮存提供指导性依据和评价标准。 相似文献
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纤维塑料筋与混凝土的粘结强度大小直接关系到构件的承载能力、裂缝开展及其它性能等。基于41个碳纤维塑料筋的拉拔试验,并综合分析其它文献的结果,对纤维塑料筋与混凝土的粘结机理、破坏机理和粘结强度进行了较为深入的研究。同时对纤维塑料筋与水泥浆和环氧树脂的粘结强度也进行了探讨。 相似文献
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塑料黏结炸药JH-94和JO-96的热安全性 总被引:2,自引:0,他引:2
借助不同升温速率(β)下,PBX-JH-94和PBX-JO-96的非等温DSC曲线的onset温度(Te)和峰温(Tp),Kissinger法和Ozawa法求得的热分解反应的表观活化能(EK和EO)和指前因子(AK),标准方法GJB 772A-97-406.1,401.2和409.1确定的比热容(Cp)、密度(ρ)和热导率(λ)以及分解热(Qd,取爆热之半)数据,用Zhang-Hu-Xie-Li公式、Smith方程和Wang-Du公式求得了PBX-JH-94和PBX-JO-96在β→0时的Te和Tp值(Te0和Tp0)、热爆炸临界温度(Tb)、绝热至爆时间(tTIad)、厚度之半和半径为0.05m的无限长平板和无限长圆柱及球状PBX-JH-94和PBX-JO-96被373K环境包围的热感度概率密度函数S(T)与温度(T)的关系曲线、S(T)-(T)曲线峰值温度(Ts(T)max)及热安全度(SD)和热爆炸临界环境温度(Tacr)。结果表明,无限长平板和无限长圆柱PBX-JO-96的热安全性优于PBX-JH-94,绝热分解至爆炸的加速趋势为后者小于前者。 相似文献
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塑料自然老化力学性能的人工神经网络预测 总被引:2,自引:0,他引:2
针对塑料老化过程,利用人工神经网络方法建立自然老化力学性能时间序列的预测模型。该模型可很好地解决老化试验中数据少且统计规律不明显的问题。从给出的拉伸强度和断裂伸长率的预测例子和计算结果表明,该方法具有良好的精度,可满足工程实际对塑料老化性能预测精度的要求。同时可大量缩短试验时间,节约试验费用。 相似文献
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《Propellants, Explosives, Pyrotechnics》2017,42(8):873-882
Passively confined dynamic impact experiments on PBX1314 specimens are performed by employing aluminum jackets with split Hopkinson pressure bar. The axial and radial stress history curves are measured in the experiments, and the characterizations of the behavior of PBX1314 under dynamic multi‐axial loads are studied. A constitutive relation is developed for modeling the dynamic mechanical responses of PBX1314 by using the Boltzmann superposition principle with a Prony series representation. The material parameters of PBX1314 can be obtained by fitting the modulus master curve. Detailed finite element simulations of the passively confined tests are carried out to evaluate the measure accuracy of the device to the material mechanical behavior. The correctness of the constitutive relation is verified by comparison the finite element simulations with the experiments. Good agreements are obtained. 相似文献
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粘结剂增强对TATB基PBX力学性能的影响 总被引:2,自引:0,他引:2
采用熔融共混法制备了氟聚合物/增强剂复合粘结剂体系,考察了增强剂含量对复合粘结剂体系性能的影响。动态力学分析(DMA)结果显示,增强剂的玻璃化转变温度大大高于氟聚合物,复合粘结剂体系的储能模量随增强剂含量的增加而增加。随着增强剂含量增加,复合粘结剂体系的拉伸强度明显增加。采用水悬浮法制备了TATB基高聚物粘结炸药(PBX),探讨了粘结剂增强对其力学性能的影响。实验结果表明,随着增强剂含量增加,TATB基PBX的力学性能显著提高。当复合粘结剂体系中增强剂含量为20%时,PBX的力学性能最佳:20℃和60℃下压缩强度为32.15 MPa和20.00 MPa,60℃下劈裂强度为2.84 MPa。 相似文献
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采用溶液共混法将笼形纳米粒子甲基丙烯酸甲酯基多面低聚倍半硅氧烷(MMA-POSS)与聚甲基丙烯酸甲酯(PMMA)共混制备无机/有机纳米复合材料。利用傅里叶红外光谱仪、核磁共振波谱仪和场发射扫描电子显微镜对材料进行了结构表征。场发射扫描电子显微镜观察复合物薄膜表面形态显示,当MMA-POSS含量较小时,薄膜表面均匀平整,MMA-POSS均匀地分散于PMMA基体中,复合材料的热稳定性和力学性能得到明显改善,其玻璃化转变温度(Tg)和热分解温度(Td)显著提高,POSS含量为1.0 %(质量分数,下同)时,Tg 和Td分别提高了16.9 ℃和21.0 ℃。 相似文献
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The complex shear moduli of crosslinked poly(2-hydroxyethyl methacrylate) and poly(2-hydroxyethyl methacrylate-co-methyl methacrylate) hydrogels were measured as a function of water content, temperature and frequency using dynamic mechanical spectroscopy. The effect of increasing water content on both the storage and loss moduli is to lower the temperatures at which mechanical transitions occur. There is a significant decrease in the storage moduli and increase in the loss moduli dispersions with increasing water content. These data could be well correlated by a multiple-mechanism, time-temperature superposition procedure. Between 2% and 28% water content in the copolymer sample, the relaxation spectra and shift function characterizing the glassy-rubbery state transition become independent of water content when properly referenced to the observed transition temperature. At lower temperatures where the β transition occurs, the mechanical viscoelastic spectra depend much more strongly on water content although the shift factors collapse to a single curve when referenced to the observed β transition temperature. 相似文献
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The effects of wood fibers on the rheological and mechanical properties of polystyrene/wood (PS/wood) composites were investigated. The composites with different ratios of PS and wood were prepared by means of internal mixer and, additionally, two different sizes of the wood particles were used, such as ~100 and ~600 µm. The rheological properties were studied using capillary rheometer, apparent shear rate, apparent shear stress, apparent viscosity, power law index, and flow activation energy at a constant shear stress were determined. The rheological results showed that the shear stress–shear rate variations obeyed a power law equation, and the composites exhibited shear thinning. The flow activation energy of the composites increased with the addition of wood particles. Mechanical results showed that stress at break of the composites was higher than that of pure PS, whereas the strain at break and impact strength of the composites were lower than that of PS. In addition, the mechanical properties of the present composites were improved when the small size of wood particles were incorporated. 相似文献
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The damping properties of ethylene-propylene-diene rubber (EPDM) with aliphatic hydrocarbon (C94) resin were investigated by dynamic mechanical analysis (DMA). It was found that the damping property of EPDM was improved after addition of aliphatic hydrocarbon resin. With increasing content of the resin, the main tan δ peak shifted to higher temperatures and the valid damping range in temperature was broadened. An addition of mica or NBR was found to widen the effective damping range. After addition of NBR into EPDM, the effective damping range of the blends was evidently extended in the applicable temperature region, especially when NBR content was 50 wt%. It was concluded that the NBR was incompatible with EPDM, and there existed two tan δ peaks in DMA spectra. 相似文献
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You Cai Xiao Yi Sun X. Li Q. H. Zhang S. W. Liu H. Yang 《Propellants, Explosives, Pyrotechnics》2016,41(4):629-636
The dynamic mechanical properties of PBX1314 and its binder are systematically investigated. Based on split‐Hopkinson pressure bar technique, the experimental results of PBX1314 and its binder are obtained under high strain rate. A constitutive theory is developed for modeling the mechanical response of dynamically loaded PBX1314 binder. To accomplish this aim, the PBX1314 binder is assayed by relaxation tests at different temperatures, in order to apply the time‐temperature superposition principle (TTSP) and raise the master curves, based on WLF equation. The rate dependence of mechanical response of the polymer binder is accounted for by a generalized Maxwell viscoelasticity model. The basis for this work is Mori and Tanaka's effective medium theory. The grains in this analysis are assumed to be spherical and uniformly distributed in the binder. The relaxation constitutive relations of particulate reinforced composites are investigated by Laplace transformation and the corresponding principle. The theoretical prediction coincides with experimental results. 相似文献
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聚氨酯弹性体的动态力学性能的影响因素 总被引:4,自引:0,他引:4
综述了聚氨酯弹性体动态力学性能的多种影响因素,讨论了软段类型(聚酯和聚醚)、软段相对分子质量、硬段类型(二异氰酸酯和扩链剂)、硬软段质量分数对PU弹性体动态力学性能的影响。在PU弹性体中,聚酯软段比聚醚软段的Tg高,弹性模量依PPG、PEG、PTMG软段顺序增加。 相似文献
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DNAN力学性能分析 总被引:2,自引:0,他引:2
利用Materials Studio软件计算了DNAN和TNT晶体在常温(25℃)、常压下(105Pa)的弹性模量,预估了二者受力过程中塑性变形能力的差异;通过纳米压痕试验测试了DNAN和TNT的弹性模量及塑性变形能力;采用力学性能试验机测试了其抗压性能、抗拉性能、抗剪性能,并结合分子间作用力对强度差异的原因进行了分析。结果表明,DNAN的抗压强度为5.96MPa,抗拉强度为2.57MPa,抗剪强度为0.34MPa;TNT的抗压强度为15.57MPa,抗拉强度为2.35MPa,抗剪强度为1.8MPa;DNAN和TNT在受力过程中的弹性形变均为200nm,DNAN的塑性形变为450nm,TNT的塑性形变为1 200nm,DNAN相比于TNT更容易发生脆性断裂。 相似文献