Aluminized Composition

However, it was found in later tests that aluminized Composition A was too sensitive... 

Experimentally it has been shown that the threshold pressure at which combustion instability can be induced artificially in composite proplnts by pulsing is a function of the burning rate of the proplnt (in a motor size of 5-inch diameter and 40-inch length) (Ref 45). This relationship is shown in Figs 17 and 18 for both aluminized and non-aluminized composite proplnts. It was also found that potassium perchlorate, lithium perchlorate and AN proplnts were resistant to this induced instability. Since AP composites were the only proplnts, other than double-base, which were driven unstable, the rate controlling reactions and response function are those related to AP decompn and perhaps the diffusion flame between oxidizer and binder... 

Another constraint on the ability of chlorite to transport H2O into the mantle results from its aluminous composition. Chlorites in natural ultramafic samples are close to stoichiometric clinochlore [Mg5Al2Si30io(OH)g] in composition, which contains 12.97 wt.% H2O and 18.35 wt.% AI2O3 (Table 1). Given that even fertile peridotites contain <4 wt.% AI2O3, a simple mass balance calculation yields a maximum of 2.8 wt.% H2O being contained in chloritized peridotite, if all AI2O3 is present in chlorite. 

Aluminized composition A of 92% RDX and 8% aluminium was originally intended for an annour piercing shell, but was found to be too sensitive to shock. 

For high purity calcium aluminate compositions, solid-state synthesis is still the norm [33, 34], Most CAC compounds are made by solid-state reactions between ground powders of calcium carbonate and purified alumina. The sintering temperatures depend on alumina content. More recently attempts have been made to synthesize CA compounds using processes with temperatures less than 900°C. These latter methods include sol-gel synthesis and precipitation and are important for production of high-purity homogenous powders with small grain size. 

Aluminate compositions include calcium aluminate cements, which have high chemical resistance, especially to sulfate, and is also used in refractory applications where ordinary Portland cements would be unsuitable. These same cements are used in bioceramic applications. The bioceramic applications reflect both the high mechanical strength of the calcium aluminate cements and also the biocompatibility of Ca-bearing phases, which bond well with, for example, bone. 

Further irradiations were performed with the cast double-base proplnts ARP, ALL, and AHH, and the aluminized composite CDT (Refs 76,77 85) at higher dosages (3.82 x lO R) than OGK proplnt to provide further data on the extent of degradation. Gas evolved between 2.4-3.1 X 10 R causing blisters. At the max dosage marked deterioration occurred in the tensile strength, elongation, and work to produce max stress. By the Taliani test these materials had reached the end of their safe life... 

A dark brown intermediate substance of irregular and ragged form with a lime-iron-aluminate composition (later shown to be calcium aluminoferrite)... 

Not only is a liquid phase a key process element during the formation of nearly all inorganic fibers, but it must have a solution or melt viscosity of log 2.5 (or 316) to log 3.0 (or 1000) poise at the forming temperature. Even the viscosities of YAG or aluminate compositions which are only <1 poise above their melt temperature, must be raised to, and stabilized between, log 2.5 and 3.0 poise, before continuous amorphous glass fibers can be melt spun. This commonalty among almost all fiber forming processes further underscores the importance of the liquid phase among the other phases. 

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