METAL MOLD FOR EXTRUSION FORMING, FABRICATION METHOD OF METAL MOLD FOR EXTRUSION FORMING, AND HONEYCOMB STRUCTURE FABRICATION METHOD

摘要

This metal mold for extrusion forming is provided with a raw material supply unit that has a first surface, a second surface formed opposite the first surface, and a first through hole formed going from the first surface towards the second surface; and a forming unit that has a second through hole formed so as to extend from the second surface towards the first surface and to connect with the first through hole. In addition to processing the metal material into a given shape, the metal mold for extrusion forming is characterized by having, in the forming unit, a processed surface obtained by performing the following steps: a processing step that forms a work-affected layer on the inner wall surface of the second through hole; an oxidized layer forming step that converts the work-affected layer to an oxidized layer by heating the work-affected layer and performing oxidization; and an oxidized layer removal step for removing the oxidized layer.