Ali Asadi*, Ali Sadough Vanini and Amin Jabbari
The Journal of Mechanical Science and Technology, vol. 25, no. 9, pp.2179-2184, 2011

Abstract : Lightweight laminated composites containing a ceramic front layer and a metallic backing layer were used in order to protect people, moving equipment, and mobile vehicles from high velocity impact and the increased mobility of mobile vehicles. In this study, by adding 10 vol% SiC and 500 ppm MgO nanoscale particles on the microstructure of 2 3 Al O matrix and applying optimum sintering conditions, ceramic performance against high-speed projectile impact was improved. To perform this investigation, a number of target samples with two different types of front layers (alumina and 2 3 Al O - SiC - MgO nanocomposite ceramic) were produced. Impact tests were conducted on these samples using 7.62 mm projectiles with a velocity of 820 ± 15 m/s. The amount of bulge and bending of the backing layer caused by impact tests was measured. The results of the impact tests on the samples made of 2 3 Al O - SiC - MgO nanocomposite ceramics and alumina were also compared and analyzed. The results indicate that the substitution of 2 3 Al O - SiC - MgO ceramic layer - which is proffered in this paper - instead of pure alumina ceramic layer, decreases the areal-density of the samples by at least 30% and improves mechanical properties by about a 60% increase in flexural strength and 100% growth of the energy distribution factor, which impressively increases impact energy absorption.

Keyword : Nanocomposite; High velocity impact; Ceramic; Mechanical properties; Laminated; Impact energy distribution