Ceramic honeycomb bodies and methods for then manufacture are provided. The ceramic honeycomb body comprises a bulk density of less than 210 g/L, a geometric surface area (GSA) greater than 93 in.sup.−1 (3.66 mm.sup.−1), a mechanical integrity factor (MIF) greater than 0.28%, and a back pressure factor (BPF) greater than 0.4 mm.sup.2.

A ceramic honeycomb structure having a web structure including a plurality of intersecting channel walls forming channels. The ceramic honeycomb structure has a total porosity greater than or equal to about 55%, an average channel wall thickness less than or equal to about 150 μm, a median pore diameter greater than or equal to about 10 μm, a d.sub.f less than or equal to about 0.45, where d.sub.f=(d.sub.50−d.sub.10)/d.sub.50, and a strength (MOR/CFA) greater than or equal to about 900 psi. A method of manufacturing a ceramic honeycomb structure by mixing a ceramic precursor batch composition having a median particle diameter less than or equal to about 10 μm and at least one starch-based pore former having a median particle diameter greater than or equal to about 10 μm. The method also includes forming a mixture of ceramic precursor batch composition and a starch-based pore former into a green ceramic structure having a web structure, and firing the green ceramic structure to yield a ceramic honeycomb structure.

An exhaust gas purification filter includes a cell assembly including cells each having a quadrangular cross-sectional shape and a partition wall, seal members, and a skin member. The partition wall has a porosity P1 of 50% to 70%, and the skin member has a porosity P2 of 50% to 70%, the porosity P1 and the porosity P2 satisfy a relationship P1<P2. A difference between the porosity P2 and the porosity P1 is 20% or less. The partition wall includes crossing portions, each cell has at least one part of an outer periphery defined by a corresponding one of the crossing portions, the at least one part is rounded to have a radius of curvature R, each cell has a radius r of a hydraulic diameter, the radius of curvature R and the radius r of the hydraulic diameter satisfy a relationship 0.2<R [mm]/r [mm]<1.

A plugged honeycomb structure includes intersecting porous walls extending in an axial direction between an inlet end and an outlet end of the honeycomb structure, the intersecting porous walls forming a matrix of repeating unit cells arranged in a repeating pattern. The repeating unit cells comprise: three or four channels, each channel formed by four walls, wherein the three or four channels comprise more inlet channels than outlet channels, at least one wall of an inlet channel or an outlet channel is intersected midwall by a wall, an area of an outlet channel is equal to or less than an area of any of the inlet channels, and continuous line segments extending along walls of at least three repeating unit cells. Other plugged honeycomb structures, plugged honeycomb bodies, honeycomb extrusion dies, and methods are disclosed.

An exhaust gas purification filter includes a cell assembly including cells and a partition wall, seal members, and a skin member. The partition wall has a porosity of 50% to 70%. The skin member has a thickness T of 0.3 mm to 1.0 mm. The partition wall includes crossing portions, each cell has at least one part of an outer periphery defined by a corresponding one of the crossing portions, the at least one part of the outer periphery is rounded to have a value of radius of curvature R being 0.02 mm to 0.6 mm A degree of distortion δ being a degree of change in the external dimensions of the filter in axial direction, is greater than 0 and is 1.5 mm or less. A value of a structural variable X, expressed by Equation 1 below, is 0.05 to 6, X=T×R/δ . . . Equation 1.

A honeycomb structure (110) includes intersecting porous walls (106). Inlet channels (108i) and outlet channels (108o) are formed by the intersecting porous walls (106), wherein the inlet channels (108i) comprise inlet hydraulic diameters (HDi) and the outlet channels (108o) comprise outlet hydraulic diameters (HDo). The inlet channels (108i) comprise inlet corners (220i) with inlet corner radii (Ri) and the outlet channels (108o) comprise outlet corners (2200) with outlet corner radii (Ro). A centerpost (124) is defined by adjacent opposing inlet corners (220i) of two of the inlet channels (108i) and adjacent opposing outlet corners (2200) of two of the outlet channels (108o). A first diagonal length (D1) is a shortest distance between the opposing outlet corners (220o) of the two outlet channels (108o) and a second diagonal length (D2) is a shortest distance between the opposing inlet corners (220i) of the two inlet channels (108i). The honeycomb structure (110) has certain aspect ratios D1:D2 depending on hydraulic diameter ratios HDi:HDo.

A honeycomb body comprises a matrix of intersecting porous walls forming channels. Plugs are disposed in a percentage of the channels having the second hydraulic diameter, wherein the percentage of the channels of the second diameter having a plug is less than or equal to 15%. In some embodiments, some of the channels have a first hydraulic diameter and others have a second hydraulic diameter that is smaller than the first hydraulic diameter, and may be unplugged for plugged. The porous walls can further comprise a transverse thickness of the walls Tw less than or equal to 0.20 mm, a channel density CD greater than or equal to 62 channels per cm.sup.2, an average bulk porosity % P greater than or equal to 50%, and a median pore diameter d.sub.50 ranging from between 4.0 μm and 30.0 μm.

Catalyzed particulate filters comprise three-way conversion (TWC) catalytic material that permeates walls of a particulate filter such that the catalyzed particulate filter has a coated porosity that is less than an uncoated porosity of the particulate filter. The coated porosity is linearly proportional to a washcoat loading of the TWC catalytic material. A coated backpressure is non-detrimental to performance of the engine. Such catalyzed particulate filters may be used in an emission treatment system downstream of a gasoline direct injection engine for treatment of an exhaust stream comprising hydrocarbons, carbon monoxide, nitrogen oxides, and particulates.

A particulate filter having a honeycomb structure of a matrix of interconnected porous walls including inlet cells and outlet cells defining a plurality of inlet channels and outlet channels, respectively, wherein at least a portion of the outlet cells are larger than any of the inlet cells, and a cross-sectional shape of at least some of the outlet channels is rectangular. Honeycomb extrusion dies, honeycomb bodies, honeycomb structures, and methods of manufacture are described, as are other aspects.

A ceramic honeycomb body, suitable for use in exhaust gas processing, includes a honeycomb structure having a plurality of through-channels, a first portion of the plurality of through-channels have a first hydraulic diameter dh1, a second portion of the plurality of through-channels have a second hydraulic diameter that is smaller than the first hydraulic diameter dh1, the first hydraulic diameter dh1 is equal to or greater than 1.1 mm, and the first and second portions of through-channels, taken together, have a geometric surface area GSA greater than 2.9 mm.sup.−1. Diesel oxidation catalysts and methods of soot removal are also provided, as are other aspects.