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Corresponding to the other steel grades brand：DAC-MAGIC DH-31EX 1.2344ESR W320
848ESR is a high-life chromium-molybdenum-vanadium alloy die steel, which can provide good thermal fatigue resistance, thermal wear resistance and plastic deformation resistance. Specialty: excellent toughness and ductility in all directions, excellent high temperature strength, excellent anti-tempering and softening ability, good dimensional stability of heat treatment, good processability and polishing, high purity, improve die fatigue life.
Applications
Thermal cracking is one of the most common failure mechanisms of thermal working dies (such as die casting and forging dies). and 8418 itself excellent ductility, so that it can effectively resist the generation of thermal cracking. Plus 8418 itself has excellent toughness and hardenability, the ability to resist thermal cracking can be further enhanced. if fruit cracking is not a main failure mechanism, the working hardness of the die can be increased by 2 HRC, which eliminates the occurrence of the main failure mechanism, such as thermal cracking, cracking, thermal wear or plastic deformation .8418 can significantly improve the life of the die, so it has better die economic benefits.
Chemical composition％
| C | Si | Mn | Cr | Mo | V | P | S | Co | Ni | Factory Status |
| 0.39/0.41 | ≤0.5 | 0.6 | 5.0/5.5 | 2.2/2.6 | 0.9/1.1 | ≤0.020 | ≤0.020 | 0.30/0.60 | ≤0.6 |
Annealing HB≤235 |
Soft Annealing
heated to 850℃ in a protective atmosphere, cooled to 650℃ at a cooling rate of 10℃/ h, then air cooled.
De-stress annealing
To eliminate residual stress after rough machining, the mold is heated to 650℃, held for 2 hours and then cooled to 500℃ in the furnace.
Surface nitriding
the surface after nitridation treatment has high hardness, good wear resistance and corrosion resistance, but its toughness is relatively poor. it is suggested that 480~520℃ plasma nitriding should be used. the depth of the nitriding layer of die casting die should not exceed 0.1 mm, and the depth of nitriding of hot forging die is 0.1~0.25 mm.
Electrosparking
Welding
The mold can be repaired by welding, before welding, the mold should be heated slowly and evenly to 325~375℃ preheating, if large area surface surfacing should be done in annealing state and need to be quenched and tempered again.
Hard chrome plating
After hard chrome plating, the mold must be tempered at 180℃ in time for 4 hours to avoid hydrogen embrittlement.
