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老化研究的重要性起因于推进剂安全寿命之评价。本综述之目的是广泛的叙述在文献上可得到的这方面的最新情况,其中包括双基固体推进剂和复合固体推进剂。本文包括的课题如下:1.破坏标准,2.安全寿命的估计,3.弹道特性和分解特性的变化,4.机械性能的变化,5.老化的历程。本文有18篇参考文献,作者为印度科学院的K.Kishore和G.Prasad。从广义上讲,老化就是固体推进剂在儲存过程中之“变质”,该变质导致固体火箭发动机性能的改变。通常进行的老化研究有两类:正常老化,加速老化。推进剂之加速老化就是把推进剂儲存在高溫下以减少试验时间,因而在较短的时间內即可进行预测。然而,有时外推的结果与在正常条件下观察到的变化并不一致。老化通常引起弹道性能(燃速、热值等等)和机械性质(模量、极限抗拉和抗压强度、产生裂缝和空隙等等)发生变化。达些变化可能在规定的许可范围之內,也可能超出规定范围;而且可能使火箭发动机平隐地工作但改变了性能,或者可能使发动机破坏。后一类称为“破坏标准”,
The importance of aging studies stems from the evaluation of propellant safety life. The purpose of this review is to provide a broad overview of the literature available in this area, including the development of dual-based solid propellants and composite solid propellants. The topics covered in this paper are as follows: 1. Destruction criterion, 2. Estimation of safety life, 3. Changes of ballistic characteristics and decomposition characteristics, 4. Changes of mechanical properties, 5. Aging course. There are 18 references in this paper by K. Kishore and G. Prasad of the Indian Academy of Sciences. In broad terms, aging is the “deterioration” of a solid propellant during storage, which causes a change in the performance of a solid rocket motor. There are two types of aging studies that are usually carried out: normal aging, accelerated aging. Accelerated aging of propellants is the storage of propellants at elevated temperatures to reduce the duration of the test, thus allowing predictions to be made in a shorter period of time. However, sometimes the extrapolation results are not consistent with the changes observed under normal conditions. Aging typically causes changes in ballistic performance (burning rate, calorific value, etc.) and mechanical properties (modulus, ultimate tensile and compressive strength, cracks and voids, etc.). Some of the changes may be within the prescribed allowances or may be out of the scope of the regulations; moreover, it is possible that the rocket engine will operate in a hidden but altered performance or may damage the engine. The latter category is called “Destruction Criteria.”