DH31-EX
High strength, tough and high heat check resistance hot work die steel.
DH31-EX is a hot working die steel with the best balance of strength and toughness showing the comparable softening resistance to SKD7 and twice hardenability as that of SKD61.
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Applications include:
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Aluminum Die Cast Dies
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Aluminum Die Cast Parts
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Hot Forging Dies
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Hot Pressing Dies
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Aluminum Extrusion Dies
- High hardenability
High toughness is obtained even in large size die. - High strength
High softening resistance at elevated temperature contributes to high wear resistance. - High toughness
DH31-EX has higher toughness than that of SKD61. - High heat check resistance
Excellent heat check resistance leads to longer life.
Product Brochure
PHYSICAL PROPERTIES
Coefficient of thermal expansion
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Specific heat
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Thermal conductivity
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Density
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Characteristics
Tempering hardness
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- Quenching temp: 1030°C
- T.P. size: 10H x 10W x 15L
Softening resistance
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- Holding temp.: 600°C
- Quenching temp: 1030°C x 30min. –> 150 Dia. Bar, AC
- T.P. size: 10H x 10W x 15L
Heat check resistance
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An example to improve heat check resistance (200mmm thickness air cool quenched die)
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<Test procedures>
- Specimen: 15mm
- I/Heating: 20<-> 700C
- Number of cycles: 1000 times
Toughness
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- Quenching temp: 1030°C x 30min. –> 150 Dia. Bar, AC
- T.P. size: L
Elevated temperature tensile properties
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- T.P. size: Ø 8 x 40L
Erosion resistance
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Creep properties
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Hardenability
Continuous cooling transformation curve
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Bainite hardenability
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Quenching cooling time vs. toughness
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Cooling time of mid portion from 1030°C to 300°C (min)
TP size: Ø440
Quenching temp: 1030°C
Surface Hardening Properties
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PS, PW process
- Daido Amistar’s originally developed process.
- PW process improves wear, fatigue and corrosion resistance.
- PS process improves scuffing and erosion resistance.
Machinability
- DH31-EX shows good machinability as high strength-high tough grades.
- Recommended machining conditions
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Repair Welding Conditions
- TIG manual welding condition
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BENEFITS
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