Chemical analysis and morphological studies of fly ash reveals the complex chemical constituents present as spherical particles with diameter of less than 25？μm. The constituents of fly ash are silica, alumina, iron oxide, titanium dioxide, calcium and magnesium oxide, and other trace elements. The use of thermosetting as well thermoplastic polymer matrix has been made by several workers to develop polymer matrix fly ash particulate composites by using the hard and abrasive properties of fly ash and lightweight of polymers. Such composites have poor mechanical strength, fracture toughness, and thermal stability. To overcome these shortcomings, in carbonaceous matrix, the carbon fibers were added as additional reinforcement along with the fly ash. The composites were developed with two different methods known as Dry method and Wet method. The processing parameters such as temperature and pressure were optimized in establishing the carbon matrix. Physical, thermal, and mechanical characteristics were studied. The microstructures of composites show good compatibility between fly ash and fibers with the carbon matrix. These composites have higher strength, thermal stability, and toughness as compared to polymer matrix fly ash particulate composites. 1. Introduction The spherical shaped materials blown out from the furnace during combustion of coal in thermal power stations make up 75% of ash generated. The spherules when empty are called cenospheres and when filled up with smaller spheres are known as plerospheres [1]. The cenospheres comprise of 0.5–1.0 weight percentage of the fly ash individual particles are chemically fairly homogeneous, but the pronounced compositional variation exists among particles with similar physical and structural attributes [2]. Cenospheres are compressed of nearly stoichiometric mullite (3Al2O3·2SiO2) needles bonded by aluminosilicate glass of similar composition that offers excellent thermal, elastic, and mechanical characteristics for use in thermostructural applications [3]. Elemental map study through energy filtered TEM shows the aluminosilicate-based and iron oxide based-nanoparticles are present in the fly ash [4]. Unburned organic matter during combustion of coal leaves carbon in three different forms in the fly ash [5, 6]. Fly ash contains toxic elements like Co, Pb, Ni, Cd, Cu, Fe, and Zn in trace [7, 8]. Particle filled polymer composites have become attractive because of their wide applications and low cost. Polymers such as Nylon 6 [9], Natural Rubber [10, 11], Styrene Butadiene Rubber [10], Epoxy [11, 12], Poly
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