含相稳定硝酸铵CMDB推进剂的机械感度和燃烧性能

通过测试撞击感度、摩擦感度和燃速,研究了含相稳定硝酸铵(PSAN)的改性双基(CMDB)推进剂的燃烧性能和机械感度。结果表明,PSAN可改善CMDB推进剂的机械感度;用PSAN作氧化剂,其推进剂的燃速低于RDX作氧化剂的燃速,压强指数高于后者的压强指数;1～5MPa压力范围内随PSAN在配方中含量的增加,推进剂的燃速降低,压强指数升高。     

DNTF-CMDB推进剂燃烧性能的调节

为了降低DNTF-CMDB推进剂的压强指数,研究了催化剂、NC与NG配比、增塑剂及内弹道稳定剂对其燃烧性能的影响.结果表明,芳香类铅盐与脂肪类铜盐复配能显著降低DNTF-CMDB推进剂的压强指数;降低配方中NG的含量可降低推进剂的压强指数;与NG相比,用TEGEN作增塑剂时推进剂具有更小的压强指数;与三氧化二铝相比,氧化镁作为内弹道稳定剂时降低推进剂的压强指数效果更好.     

DINA对含CL-20的复合改性双基推进剂性能影响

针对含六硝基六氮杂异伍兹烷(CL-20)的复合改性双基(CMDB)推进剂压强指数和摩擦感度较高的问题,采用对硝化棉(NC)增塑能力较强的吉纳(二乙醇硝胺二硝酸酯,DINA)作为辅助增塑剂,研究DINA对含CL-20的CMDB推进剂力学性能、燃烧性能和安全性能等的影响。结果表明,相较于使用3,4–二硝基呋咱基氧化呋咱(DNTF)配方,添加DINA的含CL-20的CMDB推进剂延伸率和抗拉强度分别提高了14.8%和1.6%,β转变温度下降1.27℃,在中高压区(10~20MPa)的压强指数下降至0.28,摩擦感度和撞击感度也得到不同程度下降。     

含CL-20的NEPE推进剂能量水平分析

用电算法对含有CL－20的NEPE固体推进剂配方的能量特性进行了对分析，并研究了在一这固含量下，配方中不同组分含量对体系能量示性参数的影响，研究结果表明：（1）与含HMX的原基础配方相比，CL－20引入和替代对高能固体推进剂NEPE体系的量能作用具有两重性，即提高能量密度和改善体系氧平衡条件。（2）无论是多铝还是少铝配方，CL－20／Al体系氧平衡值应保在0．52以上，CL－20与Al对体系的能量水平提高具有正加和作用。（3）在高铝含量的原基础配方中，单纯用CL－20替代HMX（体系氧平衡值＞0．51），发动机总得以提高。（4）在低铝含量的基础配方中，用CL－20替代HMX和减少那部分铝后，不仅使得少铝含量（Al≤8％）推进剂体系的能量水平得以显著提高，而且在某种程度上缓解了降低特征信号和提高能量及其他综合性能之间的矛盾。     

TKX-50在GAP基高能固体推进剂中的应用

为研究TKX-50对GAP基高能固体推进剂性能的影响,采用DSC-TG、50℃恒温贮存、摩擦感度、撞击感度、静电感度等方法研究了TKX-50与GAP基高能固体推进剂组分间安全性和相容性,并制备成TKX-50/GAP基高能固体推进剂药块,研究其密度、力学性能、安全性能、燃烧性能等,采用小型标准发动机研究其能量性能;通过DSC测试多种升温速率下的热分解性能,并使用Ozawa模型计算得到TKX-50的热分解活化能。结果表明,TKX-50与GAP黏合剂、AP、Al等相容性良好;TKX-50的热分解活化能为143.57kJ/mol;随着TKX-50含量的增加,25℃时TKX-50/GAP基高能固体推进剂的摩擦感度从100%降至44%,撞击感度从8.1J升至43.3J,静电感度变化不大,为16.0～42.0mJ;随着TKX-50含量的增加,25℃时TKX-50/GAP基高能固体推进剂的最大应力从0.65MPa降至0.35MPa,最大伸长率从25.5%升至34.33%,断裂伸长率从29.9%升至37.5%,模量从1.59MPa降至0.48MPa;低压段(3～9MPa)和高压段(12～25MPa)的燃速压强指数均呈现上升趋势,7MPa下静态燃速为17.2～18.0mm/s,低压段燃速压强指数为0.7～0.8,高压段燃速压强指数相对较高,最高达0.98。在6.86MPa下,动态燃速为21.07mm/s, BSFΦ165发动机实测比冲为256.7s。     

低铝含量NEPE推进剂燃烧性能研究

研究了铝粉含量为8％的NEPE推进剂。采用配浆浇铸法制备推进剂，并用恒压静态燃速仪测试了推进剂的燃烧性能。考察了NG／DEGDN的比例、AP粒度、HMX粒度对燃速及燃速压力指数的影响。发现增大NG／DEGDN的比例、减小AP粒径或增加细粒度AP含量，将提高NEPE推进剂的燃烧速度，压力指数升高；而HMX粒度降低，NEPE推进剂燃速降低，压力指数降低；不同来源的PbCO3对NEPE推进剂燃烧性能影响很大。     

六氯环三磷腈对RDX-CMDB推进剂性能的影响

为考察六氯环三磷腈(HCCT)作为降速剂对RDX-CMDB推进剂燃速、安定性、爆热、机械感度、力学性能的影响,测试了HCCT与RDX-CMDB主要组分的相容性,并采用靶线法、甲基紫法、绝热法等测试了3种不同HCCT含量的RDX-CMDB推进剂的性能。结果表明,HCCT与RDX-CMDB推进剂主要组分NC+NG及RDX的相容性较好,HCCT的加入使推进剂在2~6MPa压强下燃速降低,燃速压强指数升高,爆热降低,摩擦感度和撞击感度降低,抗拉强度及延伸率基本不变,对推进剂的化学安定性没有影响。     

提高碳氢富燃料推进剂燃速压强指数研究

研究了碳氢富燃料固体推进剂中固体组分的种类、含量、规格,燃速催化剂的种类、含量等因素对配方燃速压强指数(简称压强指数)的影响。结果表明,碳氢富燃料推进剂的压强指数随氧化剂含量的适度降低和固体碳氢燃料TQ粒度的减小而升高,当w(N9)为3%时,压强指数达到最高,以Mg作金属燃烧剂和以EM作燃烧催化剂的配方有较高的压强指数。通过优化上述因素,推进剂的压强指数达到了0.62~0.66。     

含CL-20改性双基推进剂的燃烧性能

设计了两组不同含量CL-20或RDX改性双基(CMDB)推进剂配方,研究了CL-20或RDX含量对两组CMDB推进剂燃烧性能的影响。结果表明,在2～20MPa,CL-20改性双基推进剂的燃速高于RDX改性双基推进剂的。CL-20含量越高,CMDB推进剂压强指数变大。现有的铅、铜盐和炭黑催化剂可用于调节含CL-20改性双基推进剂的燃烧性能。     

含ADN推进剂的能量特性及综合性能

为研究含二硝酰胺铵(ADN)推进剂的能量、安全、贮存及燃烧性能,根据最小自由能原理计算了含ADN推进剂的能量特性参数,采用密闭爆发器及靶线法测试其爆热及燃速,并对其吸湿性及感度进行了研究。结果表明,含ADN/Al/HMX、ADN/Al/CL-20、ADN/AlH3/HMX和ADN/AlH3/CL-20推进剂的标准理论比冲分别为2 675~2 685、2 677~2 686、2 801~2 810和2 803~2 812N·s·kg-1,采用硝酸酯增塑的惰性聚醚黏合剂体系可制备出固化正常、结构致密的含ADN推进剂。随着推进剂配方中ADN含量的增加,推进剂的爆热、吸湿性、燃速和压强指数增大,摩擦感度和撞击撞击提高,密度略有降低。     

CL-20含量及其粒度级配对NEPE推进剂燃烧性能的影响

采用静态与水下声发射法测试了CL-20含量及其粒度级配对NEPE推进剂燃速与压强指数的影响;采用DSC与TG-IR联用研究了CL-20对NEPE推进剂热分解行为的影响。结果表明,随着CL-20质量分数由42%增至50%,推进剂燃速与压强指数上升,燃烧效率提高,表明CL-20氧化能力高于GAP/硝酸酯含能黏合剂体系;随着CL-20/HMX、CL-20/Al质量比增高,推进剂燃速上升,燃烧效率上升;CL-20对推进剂燃速和压强指数的贡献高于HMX;随着CL-20/AP质量比增高,CL-20/AP混合体系分解产物氧化能力降低,燃烧反应速率降低,燃速降低;CL-20粒度级配对NEPE推进剂燃烧行为影响显著,当CL-20的粒径(d50)在5~50μm时,随着细粒度CL-20含量增高,推进剂燃速与燃速压强指数下降;当体系中存在超细粒度CL-20(d50=500nm)时,推进剂燃速与燃速压强指数随着超细粒度CL-20含量的增加而有所增加,4种粒度CL-20对NEPE推进剂燃速的贡献顺序为:粗粒度>中粒度>超细粒度>细粒度。     

Density functional theory and molecular dynamic investigations on the energetic and mechanical properties of nitrocellulose/nitroglycerin/pentaerythritol diazido dinitrate composites

Experimental researches stated that pentaerythritol diazido dinitrate (PDADN) may be used as an energetic plasticizer in propellants. To explore whether PDADN is an effective energetic additive of the nitrocellulose/nitroglycerin (NC/NG) double‐base propellant, in this study, various NC/NG/PDADN composites were constructed and investigated using the density functional theory and molecular dynamic methods. Results show that when the content of PDADN is less than about 20%, PDADN can increase the interactions between NC and NG and improve the mechanical properties of NC/NG; but when the content exceeds 20%, the interactions between NC and NG are weakened and the mechanical properties decrease. The composite with a mass ratio of 72.5/22.6/5.0 (NC/NG/PDADN) has the optimal mechanical properties. However, PDADN in this formula does not improve the energy output. As a whole, PDADN can be used as a plasticizer, but not an effective energetic plasticizer of NC/NG. This investigation provides a theoretical evaluation of using PDADN as an additive in the double‐base propellant and gives a practical guidance for designing the NC/NG/PDADN formula. POLYM. COMPOS., 38:192–198, 2017. © 2015 Society of Plastics Engineers     

New Gun Propellant with CL-20

A new propellant was designed with CL-20 as main energetic component, Force 1253 J/g and Combustion Temperature <3700 K. The mean mol. weight of reaction gases is 24.8 g/mol for this propellant type. The processing problems, continuous twin-screw extruder process or batch process, will be discussed for 7- or multi-perforated high energetic gun propellants especially using CL-20 as energetic solid. The safety tests, friction/impact sensitivity and chemical stability will be considered. The burning characteristics of the new gun propellant in the closed vessel at −40°C, +21°C and +50°C is explained. The CL-20 propellant will be compared with the JA 2 propellant. Test firing in a gun simulator, cal. 40 mm, shows the performance of the CL-20 propellant compared with the RDX formulation. The temperature coefficient of these propellants is pointed out. The result is a safe processed CL-20 propellant with high performance which can be used for further gun firing tests.     

Formulation and Characterization of a New Nitroglycerin‐Free Double Base Propellant

Double base propellants composed of nitrocellulose (NC) and nitroglycerine (NG) are widely used. However, the inclusion of liquid NG presents both stability and performance problems: the NG may migrate from the propellant in storage, and it softens the propellant at high inclusion levels. In this work, the novel nitrate ester 1,4‐dinitrato‐2,3‐dinitro‐2,3bis(nitratomethylene) butane (SMX) is considered as a replacement for NG in a double base propellant. Thermochemical calculations indicate improved performance when compared with the common double base propellant JA2 at SMX loadings above 40 wt‐%. Also, since SMX is a room temperature solid, migration may be mitigated. Both unplasticized and plasticized propellants were formulated to enable the study of the interaction of SMX with nitrocellulose. Thermal analysis of unplasticized propellant showed a distinct melt‐recrystallization curve, which indicates that a solid phase solution is being formed between SMX and NC, and that SMX would not act as plasticizer. Analysis of propellant prepared with diethyleneglycol dinitrate (DEGDN) plasticizer indicates that the SMX is likely dissolved in the DEGDN. The plasticized material also showed similar hardness and modulus to JA2. Safety characterization showed that sensitivity is similar to JA2. In short, replacing NG with SMX results in a new family of propellants with acceptable safety characteristics and which may also offer improved theoretical performance.     

纳米镍粉对Al-CMDB和CL-20-CMDB推进剂燃烧性能的影响

为了研究粒径为50nm的纳米镍粉(nano-Ni)对含Al改性双基(Al-CMDB)推进剂、含六硝基六氮杂异伍兹烷(CL-20)改性双基(CL-20-CMDB)推进剂燃烧性能的影响,通过吸收-压延的方法制备了推进剂样品,用靶线法测试了推进剂的燃速,并计算了压强指数。通过电镜扫描、火焰照片、燃烧波、熄火表面形貌及元素分析和DSC分析了纳米镍粉对Al-CMDB推进剂燃烧性能影响的原因。结果表明,在Al-CMDB推进剂中加入nano-Ni可大幅度提高推进剂燃速,降低推进剂的压强指数;当加入质量分数0.7%的nano-Ni时推进剂10MPa的燃速达到35.59mm/s,8~20MPa压强指数从0.43降低至0.17,15~20MPa出现麦撒效应。在CL-20-CMDB推进剂中加入质量分数0.5%的nano-Ni能明显提高推进剂的中低压(4~10MPa)燃速,8~20MPa压强指数约为0.01,15~20MPa出现麦撒效应。     

CL-20在推进剂和发射药中的应用

对CL-20在国内外推进剂和发射药中的研究应用进行了综述。含cL一20的推进剂虽然感度稍高,但有着输出能量高、低特征信号及燃烧产物对环境污染小等优点。CL-20作为低敏感、高能填充剂可用于制造高能、低敏感发射药,在某些推进剂和发射药配方中得到了应用。     

Burning Rate – Pressure Relationship of NG‐PE‐PCP‐based High Energy Propellants

Nitramines are known to produce lower burning rates and higher pressure exponent (η) values. Studies on the burning rate and combustion behavior of advanced high‐energy NG/PE‐PCP/HMX/AP/Al based solid propellant processed by slurry cast route were carried out using varying percentages of HMX and AP. It was observed that propellant compositions containing only AP and Al loaded (total solids 75 %) in NG plasticized PE‐PCP binder produce comparatively lower pressure exponent (η) values similar to AP‐Al filled HTPB based composite propellants. However, energetic propellants containing high level of nitramine (40–60 %) produce high pressure exponent (0.8–0.9) values in the same pressure range. Incorporation of fine particle size AP (ca. 6 μm) and change in its concentration in the propellant composition reduces η value marginally and influences the burning rate. However, such compositions have higher friction sensitivity.     

Development of Composite Solid Propellant Based on Nitro Functionalized Hydroxyl‐Terminated Polybutadiene

This paper presents an overview of a modified composite propellant formulation to meet future requirements. The composite propellant mixtures were prepared using nitro functionalized Hydroxyl‐Terminated Polybutadiene (Nitro‐HTPB) as a novel energetic binder and addition of energetic plasticizer. The new propellant formulation was characterized and tested. It was found that the Nitro‐HTPB propellant with and without energetic plasticizer exhibited high solid loading, high density, and reasonable mechanical properties over a wide range of temperatures. It was shown that the burning rate of Nitro‐HTPB propellant is up to 40% faster than that of the HTPB propellant. These results are encouraging and suggest that it should be possible to improve the ballistic performance of popular HTPB propellants through use of the studied Nitro‐HTPB binder.     

叠氮推进剂的感度和能量特性研究

对叠氮推进剂的感度和能量特性进行了理论计算,得到了采用硝化甘油/低感度硝酸酯混合体系来降低冲击感度和摩擦感度的有效方法,以及高能量叠氮缩水甘油醚(GAP)推进剂各主要组分含量。增塑剂为硝化甘油/丁三醇三硝酸酯(NG/BTTN),增塑比为2.0,Al粉、高氯酸铵(AP)和奥克托今(HMX)质量分数分别为18%、30%和22%。