Ballistic strength of opaque and transparent armor

A hierarchic order of influences on wear resistance of ceramics is adopted and applied in a modified form on recent ballistics results. The wear effects are explained by a hierarchic model that considers the micromechanical stability of grain boundaries of ceramic materials used for conducting ballistics tests. Investigations on depth of penetration (DoP) of 23 various alumina ceramics were made, and ballistic trials of all the ceramics were performed using tungsten long-rod penetrator with an impact velocity of 1335 m/s3. High micromechanical stability of grain boundaries, small grain size and high hardness result in decreased wear, whereas, lower grain-boundary stability and high hardness of the debris result in damaged and increased wear.