Better Designing and Evaluation of Insulating Foamed Ceramics
Federal University of Sao Carlos, (GEMM), (FIRE Associate Laboratory), Sao Carlos, SP, 13565-905/Brazil
Revision 05.02.2015, 12.02.2015
Volume 7, Issue 2, Pages 90 - 94
Abstract
Given the importance of energy costs and environmental concerns, insulating foamed ceramics have received much attention in recent years. This group of porous materials presents key properties such as low density and thermal conductivity, controlled permeability and high surface area allowing their use in many industrial processes aiming to reduce heat losses and energy consumption. However, they are subjected to stresses when used in use. Therefore, the understanding of the thermomechanical behaviour of these materials is a key issue for selection and design for structural applications. This paper is organized into two parts. The first one shows the effect of direct-foaming processing on the physical and morphological properties of macro-porous ceramics. The second part discusses the values of mechanical properties such as the compressive and flexural strengths, and the elastic modulus. In addition, a data compilation highlighting the relationship between porosity (P) and mechanical properties of foamed ceramics is shown. Finally, the results for the fracture toughness and the fracture energy of foamed ceramics are discussed. The paper also highlights that the understanding of the processing techniques and evaluation methods of porous ceramics are the correct path to generate suitable materials for a more sustainable environment where saving energy is a key aspect.
Keywords
foamed ceramics, environmental friendly processing, thermal insulating ceramics, mechanical properties
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