Method of making a extrusion die for honeycomb body, extrusion die manufactured by the same, and honeycomb body made by the extrusion die

摘要

A honeycomb structure extrusion die manufacturing method, an extrusion die produced by the same method, and a honeycomb structure produced by the extrusion die are provided to easily form a round part without making a broach blade or an electric discharge electrode to remove the corners crossing a slit. The honeycomb structure extrusion die manufacturing method comprises the steps of: forming a die body(10) having a die inlet face, a supply hole outlet face(12), and plural supply holes(13) penetrated from the die inlet face to the supply hole outlet face; preparing plural gib-headed pins(P) having a hexahedral head portion(34b) and a center pin portion(34a) integrated with the head portion by cutting; completing an integral plate preform(35) by integrally joining the head portions of plural gib-headed pins as a temporary pin support member(34c); and joining the front end of the center pin portion to the supply hole outlet face of the die body, while bringing each front end of the center pin portion into contact with the supply hole outlet face of the die body by matching a crossing slot part of the plate preform to the supply hole of the die body, and then cutting and removing the pin support member from the center pin portion. The center pin portion of the gib-headed pin has a cross sectional area smaller than a cross sectional area of the head portion and formed like a long rectangular parallelepiped. Four corners of the cross section are rounded.