新型高能高强度JMZ发射药的燃烧特性

为探索混合硝酸酯增塑的聚醚聚氨酯黏合剂体系的新型发射药的燃烧性能,通过密闭爆发器常规实验和高压实验．研究分析了JMZ发射药在不同压力范围的燃烧特性。结果表明,JMZ发射药在低压下的燃速压力指数较大,具有高含量RDX硝胺发射药的共同特征,但在高压下的燃速压力指数逐渐变小,与制式发射药相当,在燃速压力指数的变化过程中不存在明显的转折现象。另外,JMZ发射药在起始阶段表现出了良好的燃烧渐增性,对身管武器的应用是十分有利的。     

表面活性剂在发射药中的应用

采用密闭爆发器试验手段,对低易损性发射药的燃烧性能进行了研究。研究发现,硝胺颗粒的形状、颗粒度对发射药燃烧性能有较大的影响。化学重结晶处理的硝胺呈针状容易引起应力集中,不利于发射药燃烧性能的改善;球磨处理的硝胺呈鹅卵石状,有利于发射药燃烧性能。在配方组成及工艺参数完全相同的条件下,在一定范围内硝胺颗粒度越大。燃速越大,而且燃速压力指数也高;颗粒度减小。在一定程度上可以改善燃烧性能,但颗粒度减小到一定程度时。反而引起了高燃速压力指数的现象。用表面活性剂对细颗粒硝胺处理后,可以达到改善燃烧性能的目的。     

四种硝胺发射药燃烧规律研究

通过密闭爆发器恒压燃速仪对四种硝胺发射药在50～400MPa 压力范围的燃速测定,分析了它们的燃烧规律,发现在黑索今(RDX)基硝胺发射药中,除加入硝基胍作为燃速改良剂外,另一种化合物(二叠氮基乙基硝基胺)的加入。更有效地改善了黑索今基硝胺发射药 u-P 曲线转折的程度,并使压力指数控制在1.00左右。     

多层高能硝胺发射药研究

设计并制备出了高能硝胺圆环多层发射药,通过恒压燃速和密闭爆发器试验测试了缓燃材料对高能硝胺发射药燃速的影响;通过中止燃烧试验考察了多层发射药的燃烧稳定性.结果表明,缓燃材料可有效降低发射药的燃速,并有显著增强其燃烧渐增性,且燃烧稳定.30mm内弹道试验表明,与粒状高能硝胺发射药相比,在不增加最大膛压的前提下,高能硝胺多层发射药能使炮口动能提高15%左右.     

高能量密度化合物CL-20、DNTF和ADN在高能发射药中的应用

为将高能量密度化合物在高能高燃速发射药中得到更好地应用,通过密闭爆发器、真空安定性试验,研究了3种高能量密度化合物CL-20、DNTF和ADN对高能硝胺发射药RGD7A相容性、能量、燃烧行为的影响.结果表明,CL-20和DNTF与硝胺发射药的相容性良好,能使硝胺发射药能量和密度提高;40～240 MPa下,含CL-20、DNTF硝胺发射药的燃速加快,燃速压力指数增大.     

硝胺发射药燃速压力指数转折及其改善途径

综述了硝胺发射药燃烧方面的研究工作，从发射药配方研究角度总结了影响硝胺发射药燃速压力指数的一些基本因素，指出了改善硝胺发射药燃烧性能的一些有效途径；初步讨论了硝胺发射药燃烧改良剂的选择和使用。     

含FOX-7发射药的燃烧性能

采用常规密闭爆发器研究了含FOX-7硝胺发射药的燃速、压强指数和压强变化率。结果表明,随着样品中FOX-7含量的增加,发射药的点火延滞时间增加,燃速系数减小,燃速降低;其压强变化率的最大值及增长速率均降低。当燃烧压强小于150MPa时,FOX-7含量对发射药的压强指数没有影响,FOX-7改善发射药压强指数的能力不明显;随着燃烧压强的增加,含FOX-7发射药的压强指数降低,尤其当燃烧压强大于200MPa时,发射药的燃速压强指数显著降低。随着发射药中FOX-7含量的增加,其压强指数及燃速系数均降低,有利于发射药的稳定燃烧。     

硝胺发射药燃速匹配问题探讨

1.硝胺发射药的“反常燃烧”关于硝胺发射药的“反常燃烧”或称为不规则燃烧现象,国外曾进行过长时期的研究并作了大量报道。国外资料曾作了这样的描述“至今发射实验过的所有先进的硝胺炮药配方,都存在燃烧的不规则性。在4000～20000磅/时~2压力范围内,燃速压力指数n发生一次或几次转折或突变,压力指数大于1甚至远远大于1,不论甚么类型的硝胺均不例外;这种燃烧的不规则性,损害了其弹道效率和弹道再现性”。这段话指出了硝胺发射药“反常燃烧”     

四种硝胺发射药燃烧规律研究

通过密闭爆发器恒压燃速仪对四种硝胺发射药在５０－４００ＭＰａ压力范围的燃速测定，分析了它们的燃烧规律，发现在黑索今基硝胺发射药中，除加入硝基胍作为燃速改良剂外，另一种化合物的加入。更有效地改善了黑索今基硝胺发射药ｕ－ｐ曲线转折的程度，并使压力指数控制在１。００左右。     

硝胺发射药燃速匹配问题探讨

1.硝胺发射药的“反常燃烧”关于硝胺发射药的“反常燃烧”或称为不规则燃烧现象,国外曾进行过长时期的研究并作了大量报道。国外资料曾作了这样的描述“至今发射实验过的所有先进的硝胺炮药配方,都存在燃烧的不规则性。在4000～20000磅/时~2压力范围内,燃速压力指数n发生一次或几次转折或突变,压力指数大于1甚至远远大于1,不论甚么类型的硝胺均不例外;这种燃烧的不规则性,损害了其弹道效率和弹道再现性”。这段话指出了硝胺发射药“反常燃烧”的主要特征(n>1,n发生突变或转折)及其所产生的有害影响。     

Influence of Particle Size on the Combustion of CL‐20/HTPB Propellants

The effect of nitramine particle size on the combustion behavior of inert binder based propellants has been extensively studied for RDX and HMX, but not CL‐20. Although materials such as RDX and HMX are useful for particular combustion applications, CL‐20 has a greater potential to improve the oxygen balance and energy density of a propellant. The current work investigates the effect of CL‐20 particle size on the combustion of CL‐20/HTPB propellants down to submicrometer sizes. An influence of particle size on the burning rate and combustion mechanism is reported. The 30 micrometer formulation burning rate data showed evidence of convective burning specifically at higher pressures, but the pressure dependence was comparable to neat CL‐20 at pressures below 8 MPa. A change in the combustion mechanism of the submicrometer formulation as a function of pressure was determined to be a result of the interaction of the propellant flame and the combustion residue. Data suggested that at low pressures diffusion in terms of active cooling was dominant for the submicrometer formulation. Higher pressure data for both the submicrometer and 3 micrometer formulations suggest the degree of active cooling is decreased as the burning rate pressure exponent is near 0.5 for both propellants. The indirect evidence for the presence of a melt layer for CL‐20 propellants is discussed.     

Nitramine Solid Rocket Propellants with Reduced Signature

Solid rocket propellants containing nitramine are considerably superior to doublebase propellants, both as regards their performance and mechanical properties. The pressure exponent of non-modified nitramine propellants is n ≥ 0.9. The possibility of changing the burning rate or, respectively, the pressure exponent has, however, only been realisable to a restricted extent up till now in propellants with an increased nitramine content. In the following propellant system containing nitramine, the effects of ammonium perchlorate on burning behaviour are studied:

• ammonium perchlorate (AP)
• hexogen (RDX)
• nitroglycerin (NG), or trimethylolethane trinitrate (TMETN)
• polyurethane binder (PU)

AP concentrations already as great as 10% produce considerable changes in the burning behaviour of the propellants described above. It is possible to reduce the pressure exponent by the addition of ammonium perchlorate from n ≥ 0.9 to n ≤ 0.65. The burning rates may also be influenced with AP concentrations ≤ 20% and by varying the AP particle size by the factor of 2. All the propellants prepared were easily castable and showed exceptionally good viscoelastic properties (strain at break ε_R > 200%) in the temperature range between −40 °C to + 50 °C. The thermal chemical stability is not influenced negatively in any way by the combination of nitric acid esters and ammonium perchlorate.     

含黑索今酮的火药热分解及燃烧性能研究

用ＤＳＣ技术考察了７种含黑索今酮（Ｋｅｔｏ－ＲＤＸ）火药的热分解特性,并对其中３种进行了密闭爆发器测试。将ＤＳＣ数据对动力学方程进行拟合以求得动力学参数。从密闭爆发器测试结果转换得到了该３种火药的燃速－压力曲线,并对其进行了转折性分析。结果表明,向火药中加入Ｋｅｔｏ－ＲＤＸ可提高火药燃速并降低其热分解表观活化能。含Ｋｅｔｏ－ＲＤＸ的火药其燃速压力指数在低压区较在高压区为高。在火药中同时存在有Ｋｅｔｏ－ＲＤＸ和ＲＤＸ对火药热分解和燃烧的稳定性是不利的。仅由Ｋｅｔｏ－ＲＤＸ与双基粘结剂组成的火药,其燃速压力指数较由ＲＤＸ与双基粘结剂组成的火药为低。     

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.     

Ballistic Modification of Nitramine Propellants with Special Reference to NG‐PE‐PCP‐Based High Energy Propellants

The burning rate pressure relationship is one of the important criteria in the selection of the propellant for particular applications. The pressure exponent (η) plays a significant role in the internal ballistics of rocket motors. 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/AP/Al‐ and NG/PE‐PCP/HMX/AP/Al‐based solid rocket propellants processed by a conventional slurry cast route were carried out. The objective of present study was to understand the effectiveness of various ballistic modifiers viz. iron oxide, copper chromite, lead/copper oxides, and lead salts in combination with carbon black as a catalyst on the burning rate and pressure exponent of these high‐energy propellants. A 7–9 % increase in the burning rates and almost no effect in pressure exponent values of propellant compositions without nitramine were observed. However, in case of nitramine‐based propellants as compared to propellant compositions without nitramines, slight increases of the burning rates were observed. By incorporation of ballistic modifiers, the pressure exponents can be lowered. The changes in the calorimetric values of the formulations by addition of the catalysts were also studied.     

含N,N-二硝基哌嗪无烟改性双基推进剂的燃烧性能

以CMDB推进剂为基础,用N,N-二硝基哌嗪(DNP)替代推进剂中的RDX,研究了DNP含量、燃烧稳定剂(CaCO3、TiO2、MgO及Al2O3)、燃烧催化剂(铅盐、铅盐/铜盐、铅盐/铜盐/炭黑)对DNP-CMDB推进剂燃烧性能的影响。结果表明,DNP可明显降低无烟CMDB推进剂的燃速,当DNP完全替代RDX时,在18MPa压强下推进剂的燃速降低约68%;铅盐/铜盐/炭黑燃烧催化剂复配体系能够有效降低DNP-CMDB推进剂的燃速压强指数,使其出现平台燃烧效应。     

高能硝胺发射药的膛内基本燃烧特征

针对高能硝胺发射药在静态下燃速压力指数大的特殊燃烧性能，通过３０ｍｍ高压模拟炮试验，采用与制式单基药相对比的研究分析方法，对高能硝胺发射药在火炮膛内条件下的基本燃烧特征进行了研究分析。     

GAP高能低特征信号推进剂的燃烧性能调节

研究了硝胺种类、固体组分含量和粒度、增塑剂与GAP的增塑比及燃速催化剂对GAP高能低特征信号推进剂在11~19MPa下燃烧性能的影响。结果表明,当HMX取代推进剂样品中的RDX时,推进剂的燃速较高,压强指数从0.72降至0.63;在AP和HMX总质量分数为67.5%的条件下,随着AP质量分数由5%增至30%,推进剂燃速逐渐增大,压强指数由0.82降至0.45;减小AP粒度以及在配方中添加燃速催化剂或调节过渡金属化合物J1/J2的配比,可较大幅度地增加推进剂燃速和降低压强指数,其中,J1与J2总质量分数为3%,二者质量比为2∶1和1∶1时,推进剂的压强指数较小,分别为0.50和0.48;随着HMX粒度减小及增塑剂与GAP黏合剂的增塑比的降低,推进剂的燃速和压强指数降低。