Extrusion dies with zoned coatings, methods of fabricating such dies, and methods of manufacturing ceramic articles

An extrusion die comprising:

• a plurality of pins comprising side surfaces defining an intersecting array of slots extending axially into the die from a discharge face of the die;
• a plurality of feedholes extending axially into the die from an inlet face of the die opposite to the discharge face, wherein the feedholes connect with the slots at intersections within the die to create a flow path from the inlet face to the discharge face;
• a first coating on at least a portion of the feedholes in a first zone extending over a first axial length of the flow path;
• and
• a second coating on at least a portion of the side surfaces of the pins in a second zone extending over a second axial length of the flow path,
• wherein the first coating is different than the second coating,
• wherein the first coating is applied over the second coating or directly to a base material of the extrusion die, or both,
• wherein the second coating is applied over the first coating or directly to the base material of the extrusion die, or both,
• wherein at least one of the first coating or the second coating is applied directly to the base material of the extrusion die, and
• wherein the second zone transitions to the first zone at an overlap zone at which the second coating is applied over the first coating and a thickness of the second coating tapers in an axial direction toward the inlet face until only the first coating is present.

An extrusion die comprising:

• a plurality of pins comprising side surfaces defining an intersecting array of slots extending axially into the die from a discharge face of the die;
• a plurality of feedholes extending axially into the die from an inlet face of the die opposite to the discharge face, wherein the feedholes connect with the slots at intersections within the die to create a flow path from the inlet face to the discharge face;
• a first coating on at least a portion of the feedholes in a first zone extending over a first axial length of the flow path;
• and
• a second coating on at least a portion of the side surfaces of the pins in a second zone extending over a second axial length of the flow path,
• wherein the first coating is different than the second coating,
• wherein the first coating is applied over the second coating or directly to a base material of the extrusion die, or both,
• wherein the second coating is applied over the first coating or directly to the base material of the extrusion die, or both,
• wherein at least one of the first coating or the second coating is applied directly to the base material of the extrusion die, and
• wherein the first coating is applied along an entire length of the flow path from the inlet face to the discharge face, and the second coating is applied over at least a portion of the first coating such that the second zone corresponds to the portion covered by the second coating and the first zone corresponds to a non-covered portion.

An extrusion die comprising:

• a plurality of pins comprising side surfaces defining an intersecting array of slots extending axially into the die from a discharge face of the die;
• a plurality of feedholes extending axially into the die from an inlet face of the die opposite to the discharge face, wherein the feedholes connect with the slots at intersections within the die to create a flow path from the inlet face to the discharge face;
• a first coating on at least a portion of the feedholes in a first zone extending over a first axial length of the flow path;
• and
• a second coating on at least a portion of the side surfaces of the pins in a second zone extending over a second axial length of the flow path,
• wherein the first coating is different than the second coating,
• wherein the first coating is applied over the second coating or directly to a base material of the extrusion die, or both,
• wherein the second coating is applied over the first coating or directly to the base material of the extrusion die, or both,
• wherein at least one of the first coating or the second coating is applied directly to the base material of the extrusion die, and
• wherein the second coating is applied along an entire length of the flow path from the inlet face to the discharge face, and the first coating is applied over at least a portion of the second coating such that the first zone corresponds to the portion covered by the first coating and the second zone corresponds to a non-covered portion.