The Thermal Expansion, Elastic and Fracture Properties of Porous Cordierite at Elevated Temperatures

The properties that determine the thermal shock resistance in materials are reported for porous cordierite, a leading candidate material for the fabrication of diesel particulate filters. Fracture toughness and slow crack growth tests were performed on test specimens obtained from the walls of diesel particulate filter monolithic substrates using the double-torsion test method at temperatures between 20 degrees C and 900 degrees C. The thermal expansion and elastic properties were characterized between 20 degrees C and 1000 degrees C. The role of the microstructure of porous cordierite in determining its unusual thermal expansion and elevated temperature Young's modulus and fracture toughness are discussed.