无铝低燃速NEPE推进剂的燃烧性能

采用水下声发射法测定了无铝低燃速NEPE推进剂的燃速,研究了增塑剂种类、高氯酸铵(AP)与奥克托今(HMX)含量、AP粒度级配以及降速剂对无铝NEPE推进剂燃烧性能的影响。结果表明,通过选择合适的增塑剂、调整AP/HMX的相对含量、AP粒度级配以及采用有效的降速剂可使推进剂基础配方在3.5MPa下静态燃速达到4.0~5.5mm/s,2~5MPa下静态压强指数可降至0.30以下;NEPE推进剂燃烧时,NO2的生成速度越慢或NO2的含量越低,则推进剂的燃速越小,反之则越高。     

降速剂及其作用位点对丁羟四组元推进剂燃烧性能的影响规律

为研究降速剂对丁羟四组元推进剂燃烧性能的影响规律,将典型季铵盐和金刚烷衍生物两种高效降速剂引入核壳结构铝基复合颗粒Al@HMX和AP@Al,使其分别作用于HMX颗粒内部和AP颗粒表面,制备了4种含降速剂的铝基复合颗粒(Al/A@HMX,Al/B@HMX,AP@Al/A和AP@Al/B);采用扫描电子显微镜对样品形貌进行了表征;采用高速红外相机拍摄推进剂燃烧过程的火焰红外照片,并对推进剂的爆热、密度、点火延迟时间和燃速进行了测试。结果表明,加入惰性降速剂会导致推进剂爆热降低,而Al@HMX复合颗粒能部分抵消这一现象,使推进剂爆热值增加了338J/g;降速剂能够抑制AP和HMX的热分解过程,使达到AlO辐射峰值前维持低强度的“平台段”;而引入Al@HMX后,推进剂的点火延迟时间比基础配方减小49.4%;在10～20MPa范围内两种降速剂均能有效降低推进剂燃速,在此基础上采用Al@HMX可使含季铵盐丁羟四组元推进剂20MPa下的燃速降低7.1mm/s(38.4%),压强指数降至0.25;当降速剂作用于AP表面时,含质量分数1%季铵盐的推进剂在20MPa下燃速可降低5.0mm/s(27.3%)...     

桥塞投放工具用低残渣低燃速复合推进剂

为改进我国第一代桥塞投放工具用复合推进剂燃烧残渣率大和燃速高的缺点,以KNO3/AP/HTPB体系为基础设计了一种桥塞投放工具用复合推进剂.研究了不同种类降速剂、AP粒度以及催化剂对该推进剂的燃速、残渣率以及燃烧稳定性的影响.结果表明,降速剂草酸铵对复合推进剂有较好的降低燃速和残渣率的作用,AP粒径的增加有利于降低推进剂的燃速,加入催化剂可改善此推进剂燃烧稳定性.此复合推进剂经数百次油井桥塞座封施工证实,具有低残留、低燃速的优点,其综合性能显著优于国内第一代产品,达到国外先进水平.     

高能低燃速NEPE推进剂的研究

采用调节 NEPE推进剂的配方组分、添加降速剂等手段进行了一系列降低燃速的研究。研究结果表明 ,增大 AP粒径、降低 NG/DEGDN的比例、适当降低 AP含量、添加少量降速剂 ,可达到降低燃速的目的。通过对 NEPE推进剂配方组分的调节 ,在没有添加降速剂时 ,其 4.0 MPa下燃速可达到 4.7mm/ s,并且实测标准比冲可达到 2 2 39.3N·s/ kg。     

HTPB/AP/Al复合推进剂燃速降速剂研究

通过测定5．1MPa压强下HTPB／AP／Al复合推进剂药条静态燃速和BSF075mm、BSF0165mm标准发动机实验，研究了（NH4）2C2O4，LiF，CaCO3，SrCO3及季铵盐等燃速调节剂对推进剂燃烧性能、能量性能等的影响。结果表明，季铵盐降速效率最高，季铵盐与碳酸盐组合使用可使固体质量分数为87％的推进剂在5．1MPa压强下的静态燃速降至3mm／s左右。BSFΦ75mm发动机测试表明，含季铵盐与碳酸盐组合降速剂的推进剂配方在3．45～12．17MPa压强范围内的压强指数为0．2，达到了平台推进剂水平，密度比冲较相近燃速的含草酸铵推进剂高2．8％，且内弹道曲线更稳定。     

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。     

一种低燃速和低压力指数丁羟固体推进剂的研究

采用新型降速剂JS-1制备了一种低燃速、低压力指数、高比冲的丁羟固体推进剂,与常用降速剂草酸铵相比,JS-1不仅具有较高的降速效率,还使推进剂压力指数更低。标准发动机BSFΦ127测试结果表明,所研制推进剂燃速为4.78~4.93mm/s(20℃,8.0MPa)时,4~12MPa工作压强下燃速压力指数为0.23。推进剂在20℃下抗拉强度为0.694~0.835MPa,最大伸长率为50.1%~62.3%。全尺寸发动机试车各项指标均满足设计要求。     

内弹道稳定剂对中高燃速RDX-CMDB推进剂燃烧性能的影响

以一种中高燃速改性双基推进剂配方为基础配方,添加不同粒度的Al_2O_3及不同品种的内弹道稳定剂,研究了6~20MPa下推进剂燃速和燃速压强指数的变化规律,并对其燃烧机理进行了分析。结果表明,添加Al_2O_3后推进剂的燃速降低,且随着压强的升高,燃速降低的幅度减小;不同品种的内弹道稳定剂对燃速及燃速压强指数降低和提高的幅度不同,TiO2提高了推进剂高压段的燃速,MgO几乎不影响推进剂燃速,而Al_2O_3、ZrO_2均降低了推进剂的燃速。添加不同粒度的Al_2O_3后,均使燃烧表面的催化剂含量(浓度)降低,改变了催化剂的催化效率,从而导致添加芳香铅A催化剂的推进剂中Al_2O_3粒径分别为10μm和2.5μm时,燃速相应降低0.25mm/s和1.25mm/s。不同品种的内弹道稳定剂对燃烧表面催化剂含量、分散均匀性、催化活性的影响不同,TiO_2、MgO的活性高于Al_2O_3和ZrO_2,从而表现出添加TiO_2、MgO的推进剂燃速高于添加Al_2O_3、ZrO_2的推进剂。     

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。     

AP和铝粉对AP-CMDB推进剂燃烧性能的影响

通过测定推进剂不同压强下的燃速和压强指数,研究了高氯酸铵(AP)和铝粉的粒度及含量对AP-CMDB推进剂燃烧性能的影响.结果表明,减小AP粒度和增大铝粉粒度均能有效提高AP-CDMB推进剂的燃速,推进剂在10～20 MPa压强范围内的燃速压强指数随AP和铝粉粒度的减小而明显增大;铝粉的质量分数低于14%时,调节不同比例的AP和铝粉含量对AP-CMDB推进剂的燃烧性能影响不明显,铝粉的质量分数高于14%时,由于铝粉燃烧不完全导致推进剂的燃速降低.     

超细CuCr_2O_4粉体的制备及表征

以Cu(NO32)·3H2O、Cr(NO3)2·9H2O和柠檬酸为原料,采用柠檬酸配位法合成了超细CuCr2O4催化剂,用XRD、SEM对产物进行了表征,用DTA研究了CuCr2O4对高氯酸铵(AP)热分解性能的影响,测量了加入CuCr2O4后CMDB推进剂的燃速。结果表明,在最佳合成条件下(即nCu∶nCr=1∶2,温度700℃)可制得纯四方尖晶石型CuCr2O4。加入超细CuCr2O4后,AP的高温分解温度提前至339.6℃,CMDB推进剂在6MPa下的燃速从35.84mm/s提高到61.00mm/s,压强指数从0.62降低到0.14。     

超细CaCO3与金属氧化物M2O3对Al/AP/HTPB推进剂燃烧的催化协同效应研究

对超细及市售ＣａＣＯ３在低含量（≤１％）的情况下对丁羟推进剂燃烧性能的影响进行了研究，结果发现ＣａＣＯ３低含量时可提高推进剂的燃速且超细ＣａＣＯ３比市售ＣａＣＯ３的催化效率高。进一步研究了超细ＣａＣＯ３与金属氧化物Ｍ２Ｏ３组合对推进剂燃烧的催化作用，结果表明两者有协同效应，其组合的燃烧催化效果较各自单独使用的催化效果要好。     

B/Fe_2O_3/NC复合物的制备及其对HTPB/AP推进剂性能的影响

为改善硼粉(B)的性能和纳米氧化铁(Fe_2O_3)在固体推进剂中的分散性,用静电喷雾法制备了B/Fe_2O_3/NC复合物,采用扫描电镜(SEM)表征了复合物的表面形貌,用TG-DSC分析了复合物的热性能及其对HTPB/AP推进剂热性能的影响,并用燃速测试和密闭爆发器实验研究了该复合物对HTPB/AP推进剂燃烧性能的影响。结果表明,所制备的B/Fe_2O_3/NC复合物均以团聚体的形式存在,复合物中B的活性提高,其氧化反应温度提前;团聚硼粉对HTPB/AP推进剂燃烧性能的改善效果明显优于原料硼粉;加入Fe_2O_3后,会进一步改善含硼推进剂的燃烧性能,而且随Fe_2O_3含量的增加,在密闭爆发器中HTPB/AP推进剂达到最高压力所需的时间逐渐减小。当Fe_2O_3的质量分数为8%时,推进剂在常压空气中的燃速最大,为不添加B/Fe_2O_3/NC复合物的HTPB/AP推进剂的2.77倍。B/Fe_2O_3/NC复合物对推进剂的热分解具有一定催化作用,且随Fe_2O_3含量的增加催化作用增强。     

高能单元推进剂化学结构和热分解特征与燃速的相关性

利用以准一维气相反应流为基础的固体推进剂稳态燃烧模型,研究了高能单元推进剂AP、HM X、RDX、CL-20和NQ的化学结构、热分解特征与燃烧性能的相关性。改进了高能单元推进剂燃速预估模型,使其可由高能单元推进剂的化学结构和基本热分解特性出发,预估单元推进剂的燃烧性能。通过与实测燃速的比较,验证了模型假设的合理性。     

Plateau Burning Characteristics of AP Based Azide Composite Propellants

The site and mechanism by which iron oxide catalyst acted to enhance burning rate and produced plateau burning behavior at high pressure was studied. The condensed phase chemistry study was conducted by isothermal thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), and rapid-scan FTIR spectroscopic technique. Uncatalyzed ammonium perchlorate (AP) based azide composite propellant showed unstable combustion at relatively lower pressure region. The heat balance at the buring surface would be unstable at these pressures. However, iron oxide altered the burning property of the propellant and enhanced the burning rate with the plateau-mesa burning characteristics. Such pressure insensitiveness of the burning rate indicated that the condensed phase chemistry played important role in the catalytic mechanism of action. According to the microrocket motor tests, physical effect, melted fuel binder covered the AP particles and prevented the further decomposition of AP, had not affected the plateau burning. Fe₂O₃ was more effective on the burning rate augmentation than Fe₃O₄. However, the pressure exponent of the burning rate point of view Fe₃O₄ was favored catalyst to the propellant used here.     

Ammonium perchlorate-based composite solid propellant formulations with plateau burning rate trends

This paper presents burning rates as a function of pressure of several propellant formulations based on ammonium perchlorate (AP) and hydroxyl-terminated polybutadiene cured by isophorone diisocyanate, many of which exhibit significantly low (nearly zero or negative) values of the pressure exponent of the burning rate in distinct pressure ranges, termed as plateau burning rate trends. The propellants contain a bimodal distribution of AP particles with the size of the coarse and fine particles within narrow ranges whose mean values are widely separated. Two mean sizes of fine particles were considered for the propellant formulations in the present work, namely, 5 and 20 μm. These choices are based on the mid-pressure extinction behavior exhibited by the matrix of fine AP and binder contained in the propellants but when tested alone over a wide range of fine AP size and pressure. The propellants that include the fine AP/binder matrixes exhibiting a mid-pressure extinction, in turn, exhibit the plateau burning rate trends within the corresponding pressure ranges. A plateau is also observed at elevated pressures in the burning rates of some formulations, which is related to the diminishing relative importance of the near-surface leading-edge region of the oxidizer/fuel diffusion flame in the gas-phase combustion zone. The choice of the coarse AP size influences the exact pressure range within the mid-pressure extinction domain of the matrix where the propellant exhibits the plateau burning rate trends. __________ Translated from Fizika Goreniya i Vzryva, Vol. 43, No. 4, pp. 73–81, July–August, 2007.     

CaCO_3/PVC体系灰分含量测定方法的改进

采用二步法灼烧CaCO3/PVC体系,对其灰分的组成和灼烧过程中发生的反应进行了研究,并与一步法灼烧进行了对比。结果表明:①二步法灼烧过程中,CaCO3与HCl发生了复分解反应,且CaCO3的分解温度会降低,灰分含量的测量结果离散度较大;②采用一步法灼烧CaCO3/PVC体系,得到的灰分含量离散度较小,且与CaCO3含量呈一次函数关系,比二步法灼烧更合理,更具实用性。     

Burning Rate Augmentation of BAMO Based Propellants

Thermal decomposition and the burning properties of BAMO based propellants with HMX or AN/HMX have been investigated. The heat generated by the azide binder decomposition initiated and accelerated the thermal decomposition of HMX and AN. Ammonium perchlorate (AP) and lead stearate with carbon black significantly altered the mechanisms of the thermal decomposition and the burning properties of the HMX based propellants. AP showed an increase in burning rate with a slight decrease in burning rate pressure exponent. The lead catalyst yielded high value of the burning rate with the lowest pressure exponent. The ammonium dichromate also influenced the mechanisms of the thermal decomposition and the burning properties of the AN/HMX samples. The combination of ammonium dichromate and copper chromite was the most effective on the burning rate augmentation of AN/HMX based propellants. AN sublimed and evaporated from the condensed phase and mainly reacted exothermically in the gas phase HMX and AN/HMX based propellants showed smokeless burning characteristics in the small rocket motor combustion tests.     

铜铬类催化剂对HTPE低易损推进剂燃烧性能的影响

采用差示扫描量热仪(DSC)研究了铜铬类燃速催化剂(亚铬酸铜CC01和铜铬复合氧化物CC02)对端羟基聚醚(HTPE)低易损推进剂中的高氯酸铵(AP)、改性硝酸铵(AN)、HTPE黏合剂体系热分解性能的影响。结果表明,加入少量的CC01和CC02均使AP高温分解峰温明显降低了16和29.7℃,AP高温分解活化能依次降低了16.65和22.59kJ/mol,均可提高AP的高温分解反应速率。CC01和CC02均使AN的热分解峰向低温方向依次前移了52.3和53.6℃,均降低了AN的分解活化能,使AN的热分解反应速率提高了3~4倍。CC01和CC02对HTPE黏合剂体系的热分解影响较小。在AP/AN/Al/HTPE低易损推进剂中,分别添加质量分数0.5%的CC01和CC02可显著提高HTPE低易损推进剂在3~15MPa下的燃速,可使推进剂在7MPa下的燃速分别提高34.1%和43.4%,但CC01和CC02对HTPE低易损推进剂在3~9MPa下的压强指数几乎无影响,而9~15MPa下的压强指数有所降低。     

Thermal and Combustion Properties of 3,4‐Bis(3‐nitrofurazan‐4‐yl)furoxan (DNTF)

Thermal decomposition of melted 3,4‐bis(3‐nitrofurazan‐4‐yl)furoxan (DNTF) in isothermal conditions was studied. The burning rates of DNTF were measured in the pressure interval of 0.1–15 MPa. The thermal stability of DNTF was found to be close to the stability of HMX, while the burning rate of DNTF was close to the burning rate of CL‐20. The thermocouple measurements in the combustion wave of DNTF showed that combustion of DNTF was controlled by the gas‐phase mechanism. The DNTF vapor pressure was determined from thermocouple measurements and agreed well with data obtained at low temperatures under isothermal conditions.