Effects of Sodium and Iron on the Thermo-Mechanical Properties of Porous Cordierite Traps for Diesel Engines

Porous cordierite samples were contaminated separately with sodium, a n d iron, 1 wt% and 3 wt % respectively, an d then thermally aged at 800 °C. 1000 °C a n d 1200 °C for 3 hours. Young's modulus. flexural strength and thermal expansion coefficients were measured and compared with those of the uncontaminated materials. Besides structural changes, both contaminants had an adverse effect on the thermo-mechanical properties of the base cordierite, resulting in lower flexural strength and higher thermal expansion. Especially in the case of t he Na-contaminated samples after the thermal treatment at 1200 °C the base properties were found to be greatly affected.