impact behavior of ceramic-metal armour by al2o3-nano sic nano composite

abstract : alumina (al 2 o 3 ) is one of the most practical ceramics used in making ceramic-metal armours. to improve the properties of alumina, some other materials are added to it. in this paper, sic material as nano powder is added to alumina, and four armour samples of this new ceramic with different volume fractions (v.f. ) including 0%, 5%, 10% and 15% of sic particles are made. then, the samples are warmed up by hot press and their fracture toughness, bending strength and density are measured. then, it is found that the armour sample made of alumina with v.f. of 10% of sic particles shows more desirable properties as compared to the other armour samples. so, the computer simulation and ballistic test are done using alumina with v.f. of 10% of sic particles and the obtained results are compared with those of ballistic test of pure alumina. in the simulations, it is observed that the pure alumina with the thickness of 10 mm and aluminum substrate of thickness 4.8 mm is broken due to the normal impact of a projectile with 800 m/s speed, but the new armour made of the present new ceramic is able to withstand the same conditions and no fracture is observed after impact. the ballistic tests were also done using the present new ceramic-aluminum armour samples with ceramic thicknesses of 6, 8 and 10 mm, respectively to determine the smallest thickness at which the fracture is occurred. it was found that the armour with the ceramic layer thickness of 6 mm got fractured, whereas the others were able to withstand the conditions of the ballistic test.