Various Methods of Processing Silicon-Based Composites for Armor Applications.

摘要

Silicon-boron carbide compositions containing 10to 20wt% B4C were fabricated for ballistic evaluation against fragments and small arms projectiles. Fabrication was carried out by a variety of processing techniques to evaluate potential process technology. Among all the techniques investigated,hot pressing and liquid-phase sintering are the most promising with respect to density,microstructure,ease of fabrication,and yield rate. The hot-pressing parameters are established to be 1370 C for Si-10wt% B4C and 1440 C for Si-20wt% B4C,while the corresponding processing parameters by the liquid-phase sintering technique are 1410 C and 1520 C. For scale-up operation,the most appropriate composition was found to be Si-20wt% B4C due to minimum shape changes in the finished specimens. Cold forming of flat plates and complex shapes had been successfully achieved by a slip casting process. Ballistic evaluation indicated that low density Si-20wt% B4C compositions provide protection against fragments and small arms ball projectiles comparable to that of hot-pressed boron carbide. (Author)