Study Of The Surface Modification Of Silicon Type Delay Composition’s Original Material

In order to improve the delay accuracy and storage performance of the silicon delay composition, the surfaces of Pb3O4and Si are modified by FPM2602, NBR and chemosynthetic SiO2separately. After modification, Pb3O4and Si are characterized by scanning electron microscope (SEM), Fourier Transform Infrared Spectroscopy (FTIR), X ray diffracmeter (XRD) and thermogravimetry (TG). And then the silicon delay composition is synthesized from modified reagents and other materials at a specific ratio. The delay composition is tested in an aluminium tube of2mm charge diameter and15mm length with350MPa pressing pressure to attain the delay time. The conclusions are as follows:(1) Characterizing and analyzing the modified reagents respectively, we can find that FPM2602, NBR and silica have some impacts on the surface property of the Pb3O4and Si. Among these researches, by means of thermogravimetry, it is found that compared with raw Pb3O4, the temperature of Pb3O4modified by FPM2602and NBR at the maximum weight loss rate increases by32.54℃and39.45℃respectively, and the thermostability of Pb3O4has been improved.(2) There is no obvious fluctuation of delay accuracy between the unmodified silicon delay composition and the Pb3O4and Si modified by FPM2602.The average combustion time of the modified Pb3O4and Si increases by18.08%,6.14%and the average combustion rate decreases by14.79%,3.28%respectively. Similarly, the delay accuracy of Pb3O4and Si modified by NBR almost has no difference with unmodified ones. The average combustion time of the modified Pb3O4and Si increases by13.62%,2.92%and the average combustion rate decreases by13.62%,2.92%respectively.(3) Using silica produced by Stober method to modify Pb3O4and Si and mixing the modified ones with other materials to prepare the delay composition, after the delay time test, we find that the delay composition prepared by modified Pb3O4cannot be ignited. The other finding is that the average combustion time of the delay composition prepared by modified Si increases by40.50%and the average combustion rate decreases by30.37%.