MECHANICAL PROPERTIES ENHANCEMENT OF BORON CARBIDE BASED ARMOUR MATERIALS

Abstract

<p>Lightweight armor materials made from ceramics have become a great interest in the past decades.  There have been many research efforts to develop the high-performance ceramics for this particular application. Boron carbide (B₄C) is one of the promised candidates due to its extraordinary hardness, wear resistance, chemical inertness, ultra-lightweight, and its high resistance to radiation.  However, the strong covalent bonding nature of B₄C makes it hard to be sintered.  Sintering at high temperatures and the presence of impurities can also result in grain coarsening. One of the methods being used to overcome the problems is to introduce Boron (B) as a sintering aid into raw materials of B₄C.  To evaluate the effects of B addition on the sinterability of B₄C, B₄C powders were ball-milled with B powders in different ratios and the mixtures of B₄C and B were processed by spark plasma sintering technique. Density and toughness of the as-sintered materials were increased along with increasing B content in the range from 1 wt% to 7 wt% while hardness and strength of the samples were also increased when the percentage of B addition is up to 5 wt%.</p>