Experimental Studies On The Storage Stability Of Silicon Delay Composition

In this paper,the object of study was delay composition,which mass ratio of Pb3O4 to Si is 2:1.the combustion temperature and burning velocity of the delay composition were measured under different pressure by thermocouple method and photoelectric method.Under optimal loading pressure,the relationship between the delay time and the storage time of the delayed composition was measured by combining the photoelectric method with the 71℃ storage method.Based on the experimental results,the effect of Pb and Se as additives of 2%on delay time was analyzed.Finally,by means of XRD and TG-DSC,the composition change and reaction mechanism in the process of delay storage were analyzed,and the reaction mechanism of Pb and Se on delay time was obtained.Through the above work,the following conclusions are drawn:(1)In the range of 80-200MPa loading pressure,the combustion temperature within the errors had a slight fluctuation with the change of the loading pressure;as loading pressure increasing,the average burning velocity of the delay composition had a positive linear relationship to the loading pressure,the delay accuracy gradually increased at the beginning,reached the best at 170MPa and then decreased.(2)With the increase of storage time,the burning velocity and the combustion accuracy of the delay medicine without additives were decreased.In the case of the composition with Pb added,the burning velocity is 93.5mm·s-1 higher than that of the delayed composition without additives under the condition of no storage.In the storage process,the overall combustion rate is relatively stable and the delay accuracy is relatively stable.Compared with the other two agents,the addition of Se has less influence on the burning velocity,and the burning velocity and delay accuracy are the most stable and the best.(3)XRD analysis showed that with the increase of storage time,the content ratio of Pb3O4-Si in the delay composition were decreased,but the mass ratio of Pb3O4-Si in the silicon delay drugs containing Pb and Se decreased less and showed a little fluctuation.(4)TG-DSC analysis found that Pb and Se may catalyze the decomposition of Pb3O4,or to a certain extent,replaced the Si with Pb3O4 occur redox reaction.Figure[22]table[8]reference[45].