چكيده به لاتين
The main purpose of this dissertation is to study the effect of nanofluid and its use in aramid fabric to investigate its effect on high speed impact test experimentally. This nanofluid is typically made by mixing nano silica and polyethylene glycol. Much research has been done to date in this field, most of which have considered variables such as silica weight weight, silica particle size, number of layers, etc. as variables. However, little research has been done on nanofluids with mixed particles, and information on this subject is limited. Therefore, in this dissertation, the additive effect of graphene oxide and graphene oxide hybrid (graphene oxide + iron oxide particles) in different weight percentages has been investigated. Hybrid graphene is a material that secondary particles are located on the surface of graphene, which can affect its properties. In this study, graphene oxide was added to two types of nanofluids containing silica fume and spherical silica. The results of the pull out test showed that graphene reduces the friction between the fibers and thus weakens the ballistic resistance of the fabric. However, graphene hybrids 0.4% increase friction by weight of the iron oxide particles on it, thus improving the ballistic resistance of the fabric. The graphene hybrid 0.4% sample performed best compared to other samples, increasing energy absorption by 56.09% compared to plain fabric and also increasing the specific energy absorption (energy absorption divided by surface density) at high speeds. Importantly, according to previous studies, a sample impregnated with silica nanofluid increases the energy absorption in the ballistic test, but due to the mass it exerts on the fabric, it always reduces the specific energy absorption . Various additives have been studied in some research that have improved energy absorption compared to silica nanofluid samples, but due to increased mass, they had less specific energy absorption than plain fabric. In this dissertation, the sample with hybrid graphene 0.4% did not change the fabric mass and increased the specific energy absorption from (j / (g / cm2)) 258.36 for plain fabric to (j / (g / cm2)) 277.26.
