Effect of Carbon Black as a Conductive Filler on The Electrical, Thermal and Mechanical Property of Epoxy
Topic(s) : Material science
Co-authors :
Bibhuti Bikash KAGYUNG (INDIA), Chandrasekher YERRAMALLI (INDIA)Abstract :
Epoxy resins are a type of thermosetting polymer used in aerospace applications due to their strength, toughness and versatility. Fiber-reinforced composites are a great substitute for traditional metals in aircraft structures. This is due to their superior strength-to-weight ratio, superior stiffness-to-weight ratio, corrosion resistance, etc. Epoxy is one of the most popular choices as matrix in such composites. Despite their numerous advantages, fiber-reinforced composites are susceptible to damage in the case of a lightning strike. Due to the insulating nature of epoxy, the massive amount of energy transferred during a lightning strike event are not properly dissipated on the surface of the structure. This leads to resistive heating, known as Joule heating at the strike area. The temperature can rise to several thousand of kelvin which is enough to cause catastrophic damage to the composite structure.
Several lightning strike protection methods are available. The most traditional way is to use a metallic foil on the surface of the composite panel. However, such metallic foils are not 100% effective. Also, these metallic foils add to the overall weight of the structure. Researchers are looking for lightweight alternatives to such metallic meshes. Carbonaceous materials are a promising aspect in this regard. Carbon nanotubes have been extensively researched due to their conductive nature. Another economical alternative is Carbon Black.
In this study, a solvent-dispersion method has been used to create a uniform dispersion of Carbon black in epoxy matrix. Using this dispersion method, a high filler volume content (up to 20%) can been achieved. These modified epoxies were fabricated and various tests were performed on them. The mechanical behaviour of the samples was determined using tensile tests. The change in strength and modulus were noted with varying filler volume fraction. Differential Scanning Calorimetry (DSC) was done to study the variation in the glass transition temperature with different filler volume fraction. The changes in the thermal and electrical conductivities with respect to filler volume fraction was also measured using Thermal conductivity meter and Electrometer respectively. The uniformity of dispersion of the fillers in epoxy was studied using Scanning Electron Microscopy with Energy Dispersive X-Ray Spectrometry (SEM/EDX) images.
Mechanical, thermal, electrical and morphological property changes of the epoxy samples were studied. The main purpose of the study was to understand the variation of the properties of epoxy resin with increasing filler volume fraction. The optimum filler volume fraction in epoxy can be used as a conductive matrix in Carbon Fiber reinforced Polymer Composites as a Lightning Strike Protection system.
Several lightning strike protection methods are available. The most traditional way is to use a metallic foil on the surface of the composite panel. However, such metallic foils are not 100% effective. Also, these metallic foils add to the overall weight of the structure. Researchers are looking for lightweight alternatives to such metallic meshes. Carbonaceous materials are a promising aspect in this regard. Carbon nanotubes have been extensively researched due to their conductive nature. Another economical alternative is Carbon Black.
In this study, a solvent-dispersion method has been used to create a uniform dispersion of Carbon black in epoxy matrix. Using this dispersion method, a high filler volume content (up to 20%) can been achieved. These modified epoxies were fabricated and various tests were performed on them. The mechanical behaviour of the samples was determined using tensile tests. The change in strength and modulus were noted with varying filler volume fraction. Differential Scanning Calorimetry (DSC) was done to study the variation in the glass transition temperature with different filler volume fraction. The changes in the thermal and electrical conductivities with respect to filler volume fraction was also measured using Thermal conductivity meter and Electrometer respectively. The uniformity of dispersion of the fillers in epoxy was studied using Scanning Electron Microscopy with Energy Dispersive X-Ray Spectrometry (SEM/EDX) images.
Mechanical, thermal, electrical and morphological property changes of the epoxy samples were studied. The main purpose of the study was to understand the variation of the properties of epoxy resin with increasing filler volume fraction. The optimum filler volume fraction in epoxy can be used as a conductive matrix in Carbon Fiber reinforced Polymer Composites as a Lightning Strike Protection system.