New Low Temperature Processing for Boron Carbide/Aluminum Based Composite Armor.

摘要

The developed Boron Carbide/Aluminum based materials are a promising alternative for the use in lightweight armor application. The advantage of B4C/A1 composite over the traditional metal armor is its ballistic limit of 80 to 90% of that for hot pressed B4C, thus similar to ceramics such as A1N or SiC. The advantage of B4C/A1 over monolithic ceramic armor is its higher toughness. The ballistic efficiency of B4C materials, relative to hot-pressed boron carbide, was found to be directly related to the initial boron carbide content, the B-C-A1 phases formed in situ, and their continuity. The highest improvement of ballistic efficiency was associated with increasing contents of B4C and A1B2 in the system. The Rapid Omnidirectional Compaction process is a suitable technique to produce nearly dense B4C/A1 cermet at the low temperature. Dense, but soft, cermets can be near-net shaped and then changed into hard, ceramic-like structure through heat-treatment. Mechanical properties of B4C/A1 cermet depend mostly on the concentration and continuity of the boron carbide phase. Colloidal processing and post densification heat-treatment can be used to further modify properties for the application at hand. Keywords: Lightweight armor, Cermets, Rapid Omnidirectional Compaction, Dispersion, Aluminum alloys, Boron carbide.