High fracture toughness metallic carbonate matrix-fiber composites

Cement is one of the most common and least expensive ceramic matrices and is widely used for buildings and infrastructure. Production processes for cement emit significant amounts of CO2, a major greenhouse gas (GHG). Several methods for making cement production more environmentally friendly have been proposed. In particular, certain binder matrices are able to chemically sequester CO2. Unfortunately, these matrices do not require very much energy to fracture once crackedthat is, these matrices are not very tough. Low toughness ceramics are particularly susceptible to service-related damage such as crack growth under static loads or cyclic fatigue. This damage results in an overall loss of material strength, which can have dangerous ramifications for the structural integrity of buildings and infrastructure. Researchers at Arizona State University have invented a new structural binding material for cement that significantly improves toughness and durability. A fiber matrix is added to the cement binder. The fiber matrix improves the toughness of cement. Iron fillings are also added to the matrix, which results in increased strength and ductility. The result is a significant improvement in cement toughness. The relationship between the amount of matrix material and cement toughness is not linear. This non-linear relationship means that smaller amounts of material produce a pronounced performance improvement. Potential Applications Ecofriendly alternative to traditional cement Building and infrastructure Construction Chemical CO2 sequestration Landfill size reduction through elimination of major source of manufacturing process waste Benefits and Advantages Durability Improved fracture toughness, strength, and ductility of concrete. Low Cost Only a small amount of matrix-fiber composite material needed to drastically improve fracture toughness for concrete. Easily integrated into existing processes. Sustainability Uses ecofriendly industrial processes to sequester CO2. Energy Conservation Reaction occurs at ambient temperatures, minimizing necessary additional energy input. Industrial Ecology Waste iron and CO2 from other processes is recycled directly into the process stream. Download Original PDF For more information about the inventor(s) and their research, please see Dr. Narayanan Neithalath's directory webpage For more information about related technologies, please see M14-242P: Carbonating a Fine Metallic Poweder and Tailoring the Micro-Structure to Develop Dense Binder Systems