Mechanical Behavior of Ceramic and Polymer Composites Reinforced with Volcanic Ashes

A study of the mechanical behavior of three composite materials under compressive, flexural, hardness and impact stress is presented in this research. The experimental work consisted on manufacturing and characterizing the composites. Firstly, the volcanic ashes, clay, water and other adherent ingredients were mixed. Then, this mixture was winterized and vitrified to obtain the ceramic matrix composite. On the other hand, the ashes were mixed with epoxy resin and polyester resin, individually, to origin two polymer matrix composites. Next, physical and mechanical tests were done to determine their physical and mechanical properties. The hardness, compressive, flexural, and impact stresses were determined and analyzed to know the mechanical behavior of the materials and to study their failure. Due to the fact that the mechanical properties of these composites are strongly affected by characteristics of their microstructure, their physical properties such as density, porosity and water absorption were evaluated. Also, an analysis of the materials’ microstructures in the scanning electron microscope and X-ray diffractometer was made. Finally, it could be observed that finer grain size helped reduce the volumes of open pores and stresses that develop at grain boundaries due to anisotropic expansion and contraction in the microstructures. Ceramic composites failed because of their low fracture toughness. However, this mechanism of failure in the polymer matrix composites was different, as the materials were subject to stresses. Considerable heating occurred near some pores and the inter-relationships between fatigue and creep. The results indicate that these products can be used like an added value in the industrial sector.