Honeycomb filter
A honeycomb filter 1 is constituted by integrating a plurality of honeycomb segments 12 including a large number of through channels 3 partitioned by partition walls 2 and extending through an axial direction. The honeycomb filter 1 is characterized in that a thermal conductivity, strength, or strength/Young's modulus ratio of a honeycomb segment 12 I disposed in a central portion is high, or a porosity, average pore diameter, or (porosity×(average pore diameter) 2 ) of a wall portion is small with respect to a honeycomb segment 12 O disposed in an outer peripheral portion. The honeycomb filter is used in a filter or the like for capturing particulates in an exhaust gas, superior in regeneration efficiency, and capable of simultaneously achieving durability and low pressure loss.
1. A honeycomb filter constituted by integrating a plurality of honeycomb segments including a large number of through channels partitioned by partition walls and extending through an axial direction, wherein with respect to the honeycomb segments disposed in an outer peripheral portion of the honeycomb filter, the honeycomb segments disposed in a central portion are high in at least one property selected from a group consisting of a thermal conductivity, a strength, and a strength/Young's modulus ratio and/or are small in at least one property selected from a group consisting of a porosity, pore diameter, and value represented by (porosity (%)×(average pore diameter (μm)) 2 ) of a wall portion constituting the honeycomb segment.
2. The honeycomb filter according to claim 1 wherein the thermal conductivity of the honeycomb segment disposed in the central portion is high with respect to the honeycomb segment disposed in the outer peripheral portion of the segmented filter.
3. The honeycomb filter according to claim 1 wherein the strength of the honeycomb segment disposed in the central portion is high with respect to the honeycomb segment disposed in the outer peripheral portion of the honeycomb filter.
4. The honeycomb filter according to claim 1 wherein the strength/Young's modulus ratio of the honeycomb segment disposed in the central portion is high with respect to the honeycomb segment disposed in the outer peripheral portion of the honeycomb filter.