Mechanical characterization of diesel particulate filter substrates

Test procedures for the mechanical evaluation of diesel particulate filter (DPF) substrate materials have been developed and applied for the characterization of porous cordierite under ambient conditions. Specifically the double-torsion test method was employed to characterize fracture toughness and slow crack behavior while resonant ultrasound spectroscopy (RUS) was used to determine the elastic properties of the substrate walls. A dry grinding procedure was developed to fabricate test specimens for these tests. The fracture behavior of porous cordierite was related to the pore structure inside the filter wall. Implications of the test results on the mechanical reliability of DPFs are discussed.