| 摘要 |
PROBLEM TO BE SOLVED: To suppress the generation of cracks by the heat shock caused by the thermal expansion difference between a honeycomb structure and a seal part without inhibiting the material selection of the seal part or the degree of freedom of the setting of porosity, without promoting the accumulation of PM in the seal part or without generating the irregularity in the purification function of PM between cells.SOLUTION: The differences between the respective longitudinal and lateral coefficients of thermal expansion of a honeycomb structure 10 and a seal part 13 are both below 0.5×10/°C and the differences between the individual longitudinal coefficients and the individual lateral coefficients, of thermal expansion, are below 3.5×10/°C. Further, in a case that the longitudinal and lateral coefficients of thermal expansions in the honeycomb structure 10 and the seal part 13 are respectively supposed as vectors, the difference of the angles &thetas;h and &thetas;m taken by the expansion vectors Zh and Zm being those resultant vectors with the axial direction is below 15°. |
