PURPOSE: To provide a die with toughness, abrasion resistance and anti-seizing property by forming a die body from a steel material having toughness, forming an opening part from a specified composition of graphite crystallized high chrome cast iron material, diffusion-joining and integrating them.
CONSTITUTION: This die is composed of an opening part 3 provided with an extrusion hole 4 and a die body 2 holding the opening part 3 on its circumference and both are diffused, joined, combined and integrated into one body. The die body 2 is formed from steel material having strong toughness high in fatigue strength, such as SCM material, SUT material, etc. The chemical composition in weight percentage of graphite crystallized high chrome cast iron material forming the opening part is specified as: 2.8W3.6% C; 4.5W10% Ni; 2.5W4.0% Si; 5W10% Cr; 0.5W1.5% Mn; 1.0W6.0% Mo; ≤0.1% P; 0.8% S and the balance is substantially Fe. Accordingly, abrasion resistance is prepared by M7C3 high hardness Cr carbide and Mo carbide produced in the base while part of crystallized graphite acts as lubricant and is provided with anti- seizing property.
KATAYAMA HIROAKI
MORIKAWA TAKERU
MAEYA NOBUROU
