Characterization of Epoxy based Composites for Light Weight and High Strength Applications for Air-Frame Structures

Metals are not suitable materials for aerospace applications due to their high density and therefore composite materials are used as substitute due to their light weight and high strength characteristics. Composite materials especially carbon-epoxy composites are especially strength bearing materials useful in aero space applications used as airframe structures . Filament winding process, tape wound process, and molding processes are used for fabrication of air frame structures, which are capable to mechanical loads when compared to other materials. Bi-directional carbon-epoxy composites are representative materials to filament tape wound components of air frame structure. This study is tried to analyse the fiber volume fraction of the composites with effective consolidation (low thickness) of layers by applying vacuum and pressure during curing of the laminate. Mechanical properties like tensile, flexural and inter laminar shear strength for carbon-epoxy (LY556+HT972),bi-directional composites with different process parameters to fiber volume fraction with low thickness. The results from the study have demonstrated that the composites cured with vacuum and pressure is exhibiting improvement in tensile strength, flexural strength due to high fiber volume fraction. Material have been classified into four categories based on their applications to achieve particular physical, mechanical and therm al characteristics. 1Metals, 2.Organicmaterials(polymers), 3.Cera micmaterials, 4.Composite materials. A composite is commonly defined as a combination of two or more distinct material search of which retains its own distinctive properties, to create a new material. The two distinct materials. Composites are the mixture of two materials, which in combination, offer superior properties to the materials alone. Structural composites usually refer to the use of fibers which are embedded in a plastic. These composites offer high strength with very little weight.. The two distinct materials are one is matrix and another is reinforcement embedded in the plastic. Matrix surrounds the reinforcement and protects the reinforcements impart their special mechanical and physical properties to enhance the matrix properties. A synergism produces material properties unavailable from the individual constituent materials. The matrix material can be introduced to the reinforcement before or after the reinforcement material is placed into the mold cavity allows the designer of the product or structure to choose an optimum combination. Composites are having the following advantages in terms of light weight , weight distribution, high strength to weight ratio, directional strength and stiffness, corrosion resistance, weather resistance, low thermal conductivity, low coefficient of thermal expansion, high dielectric strength, nonmagnetic and radar transparency.