Die for forming honeycomb structure and manufacturing method of die for forming honeycomb structure

A manufacturing method of a die for forming a honeycomb structure, comprising:

• a first plate-like member preparation step of forming a super hard material containing tungsten carbide and a bonding agent into a plate-like shape, followed by preliminary sintering, to prepare a first plate-like member;
• a second plate-like member preparation step of similarly forming the super hard material into the plate-like shape, followed by the preliminary sintering, to prepare a second plate-like member;
• a back pore processing step of forming back pores extending in a thickness direction through the first plate-like member;
• a sintering step of sintering the first plate-like member and the second plate-like member in vacuum at 1300 to 1600° C. for 0.5 to 100 hours;
• a bonding step of superimposing the first plate-like member and the second plate-like member after the sintering step to obtain a die precursor, and heating the die precursor at 1400 to 1500° C. for one to ten hours while applying a pressure of 10 MPa or less in the thickness direction to the contact surface of the first plate-like member and the second plate-like member;
• and
• a slit processing step of forming slits connected to the back pores in the second plate-like member after the bonding step.