The honeycomb structure forming die includes a first die in which a central region on the side of a kneaded material discharging surface has a convex region projecting toward a downstream side in an extruding direction of a kneaded material, and a ring-shaped second die. In the first die, first kneaded material introducing holes are formed and latticed first slits are formed on the side of the kneaded material discharging surface of the convex region, and in the second die, there are formed second kneaded material introducing holes and latticed second slits communicating with the second kneaded material introducing holes, and the honeycomb structure forming die has a groove region where movement of the kneaded material is performed between the first kneaded material introducing hole and the second kneaded material introducing hole, in abutment surfaces of the first die and the second die.

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 having a honeycomb structure and a peripheral skin, the honeycomb structure having walls defining a plurality of cells including peripheral cells disposed directly adjacent to the peripheral skin. One or more of the peripheral cells is at least partially defined by a first wall surface, a second wall surface, and a skin surface portion extending between the first wall surface and the second wall surface. A continuously-varying radius extends from a first tangent to the first wall surface along the skin surface portion and to a second tangent to the second wall surface. Other honeycomb bodies, structures, and extrusion dies for forming honeycomb structures are disclosed.

An extrusion die (16) including a plurality of pins (38) having side surfaces defining an intersecting array of slots (30) extending axially into the die (16) from a discharge face (34) of the die (16). A plurality of feedholes (28) extend axially from an inlet face (32) of the die (16) opposite to the discharge face (34). The feedholes (28) connect with the slots (30) at intersections (35) within the die (16) to create a flow path from the inlet face (32) to the discharge face (34). A first coating (42) is on at least a portion of the feedholes (28) in a first zone (46) extending over a first axial length of the flow path. A second coating (44) that is different than the first coating (42) is on at least a portion of the side surfaces (37) of the pins (38) in a second zone (48) extending over a second axial length of the flow path. Methods of fabricating an extrusion die (16) and manufacturing a ceramic article (100), such as a honeycomb body, are also disclosed.

A mouthpiece (10) for extruding a molding compound into a formed body which has internal channels, comprises: a mouthpiece frame (14) with a frame opening (16); a first core retaining plate (22) which is fastened in the area of an upstream end of the frame opening (16) when viewed in the flow direction (15) of the molding compound; and a plurality of longitudinal cores (28) which are axially and laterally held by an upstream end section (26) on the first core retaining plate (22). It is proposed that, furthermore, it comprises a second core retaining plate (36) which is loosely arranged downstream of the first core retaining plate (22) relative to the mouthpiece frame (14) in the flow direction (15), and in which the areas (32) of the cores (28) farther from the upstream end section (26) are arranged to be radially fixed but axially loose.

A honeycomb extrusion die comprising at least some slots (308) each with a divot (312) spaced toward a discharge surface (324) from a feedhole-slot intersection (332) and a wide portion at the discharge surface extending into the die body (358) to the divot (312) to strengthen a peripheral region of a honeycomb extrudate in a reinforcement region, and a bulk nominal section corresponding to a bulk region of the honeycomb body.

A tool die for forming a green ceramic body. The tool die has a wear resistant coating that is deposited on a substrate and has an outer or free surface having a morphology that provides a mean roughness in a range from about 0.03 μm up to about 0.8 μm Rq. In one embodiment, the wear resistant coating has multiple alternating layers of fine grained and coarse grained materials. Methods of making the tool die and wear resistant coating are also provided.

A tool die for forming a green ceramic body. The tool die has a wear resistant coating that is deposited on a substrate and has an outer or free surface having a morphology that provides a mean roughness in a range from about 0.03 μm up to about 0.8 μm Rq. In one embodiment, the wear resistant coating has multiple alternating layers of fine grained and coarse grained materials. Methods of making the tool die and wear resistant coating are also provided.

Extrusion dies and methods of manufacturing extrusions dies, the extrusion die including a first plate and a second plate. The first plate has first upstream and downstream surfaces. A first material of the first plate has a first elastic modulus. The first plate includes pins formed between a plurality of slots. The pins and slots define a discharge face for the extrusion die at the first downstream surface of the first plate. The second plate has second upstream and downstream surfaces. The second plate is joined at the second downstream surface to the first upstream surface of the first plate. A second material of the second plate has a second elastic modulus. The second elastic modulus is greater than the first elastic modulus. A plurality of feed holes extend from the second upstream surface of the second plate through the extrusion die into communication with the slots.

A die body apparatus (101) includes a first discharge member (105) configured to be bonded with respect to a base member (103) such that aligned elongated openings (209) of the base member (103) and first discharge member (105) provide a plurality of elongated feed passages placing a plurality of feed holes (106) of the base member (103) in fluid communication with a first honeycomb network of discharge slots (415) of the first discharge member (105). In further examples, methods of assembling a die body apparatus (101) includes the step of bonding a selected discharge member (105) of at least one discharge member with respect to a base member (103). In further examples methods of extruding batch material into a honeycomb body includes the steps of bonding a selected discharge member (105) with respect to a base member (103) and extruding a quantity of batch material through the die body apparatus (101) into an extruded honeycomb body with a honeycomb network of channels.