SKD61 steel customization goes beyond standard catalog sizes. Modern manufacturing needs non-standard dimensions, special surface treatments, and tight tolerances. Off-the-shelf products can’t deliver these. You might be making detailed aluminum extrusion molds. Or you need complex dies with multiple heat treatment cycles. Customized SKD61 solutions fill the gap between generic inventory and your exact specs.
1. Comprehensive Size Customization Range
Customized SKD61 steel covers almost any configuration you need:
| Category | Specifications & Features |
|---|---|
| Round Bar Configurations |
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| Plate Specifications |
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| Flat Bar Dimensions |
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Custom Blocks and Forgings
– Block production: up to several tonnes per piece
– Free-form forgings tailored to near-net shapes
– Less machining time and material costs
– Perfect for large die blocks and special tooling
This wide size range handles many manufacturing scenarios. You get compact round bars for precision tooling. Or massive die blocks for automotive stamping. Custom sizing cuts out heavy machining from oversized stock. This lowers your material costs and production time.
2. Precision Dimensional Tolerance Specifications
Consistent quality in tool steel needs tight dimensional control. SKD61 customization includes exact tolerance specs across different production methods:
Hot Round Bar Thickness Tolerances
| Diameter Range (mm) | Tolerance (mm) |
|---|---|
| 6.4–15.8 mm | ±0.038 mm |
| 15.8–77.6 mm | 0–0.10 mm |
| 77.6–103 mm | 0–0.15 mm |
| 103–181mm | 0–0.78 mm |
| 181–206.2 mm | 0–1.6 mm |
| 206.2–257 mm | 0–2.4 mm |
| 257–307.7 mm | 0–3.2 mm |
| ≥307.7 mm | 0–4.7 mm |
Hot Rolled Plate Thickness Tolerances
| Specification Range | Tolerance |
|---|---|
| ≤25.4 mm | −0.41 to 0.79 mm |
| >25.4–76 mm | −0.79 to 1.19 mm |
| >127–152 mm | −1.60 to 2.39 mm |
| >178–254 mm | −1.98 to 3.18 mm |
Machined and Ground Tolerances
– Machined tolerance: h9–h11 grade precision
– Hot rolled general tolerance: ±1–3 mm
– Precision ground bars: custom tolerances to your exact needs
These tolerance bands match international manufacturing standards. They also give you flexibility where tighter control adds real value. Precision dies need dimensional consistency. This affects part quality. Machined or ground tolerances ensure repeatability across production runs.
3. Surface Finish Options for Every Application
Surface finish affects later processing, wear resistance, and final tool performance. Customized SKD61 steel offers multiple finish options:
| Finish Type | Description | Main Benefits | Typical Applications |
|---|---|---|---|
| Hot Rolled Finish | As-produced surface from hot rolling |
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| Annealed Finish | Heat-treated to ≤255 HB hardness for better machinability |
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| Machined Finish | Precision-turned or milled surfaces to set dimensions |
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| Ground Finish | Precision ground to tight tolerances (h9–h11 or tighter) |
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| Black Finish | Protective oxide coating applied during cooling |
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| Rough Machined and Turned Options | Semi-finished to near-net dimensions |
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The right surface finish cuts your downstream processing costs. Take annealed and rough-machined blocks. They remove hardness changes and surface scaling issues common with as-rolled material. This gives you more predictable machining cycles and tool life.
4. Chemical Composition Customization and Standards Compliance
SKD61 follows set chemical composition ranges. But customization lets you specify by different international standards. You can also fine-tune for specific performance traits:
Standard SKD61 Chemical Composition (JIS G4404)
| Element | Content (%) | Main Effects |
|---|---|---|
| Carbon (C) | 0.35–0.42 | Affects hardness and wear resistance |
| Chromium (Cr) | 4.8–5.5 | Gives oxidation resistance and hardenability |
| Molybdenum (Mo) | 1.0–1.5 | Boosts high-temperature strength |
| Vanadium (V) | 0.80–1.15 | Forms stable carbides for wear resistance |
| Silicon (Si) | 0.8–1.2 | Improves hot strength and oxidation resistance |
| Manganese (Mn) | 0.25–0.5 | Adds to hardenability |
| Phosphorus (P) | ≤0.03 | Controlled to reduce brittleness |
| Sulfur (S) | ≤0.03 | Limited to ensure toughness and impact resistance |
Available International Standard Equivalents
– JIS: SKD61
– ASTM/AISI: H13
– DIN: 1.2344 / X40CrMoV5-1
– China GB: 4Cr5MoSiV1
– Russia GOST: 4Х5МФ1С
Customization by international standards (GB, DIN, ASTM, JIS, and others) matches your existing material specs and quality control procedures. Global sourcing becomes easier. You can specify composition by your local standard. This clears up any confusion in material verification and acceptance testing.
For critical jobs, composition can be adjusted within spec ranges. This optimizes specific properties. You might want higher vanadium content for better wear resistance in abrasive die uses. Or optimize chromium levels for better oxidation resistance in high-temperature forging dies.
5. Heat Treatment Condition Options
Heat treatment shapes SKD61’s performance. Customized heat treatment conditions give you material optimized for your specific use:
| Heat Treatment Condition | Description & Key Benefits | Hardness |
|---|---|---|
| Annealed Condition |
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≤255 HB |
| Hardened and Tempered Condition |
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48–52 HRC |
| Custom Heat Treatment Cycles |
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Varies—application specific |
Material in hardened and tempered condition removes risks with in-house heat treatment of large die blocks. No non-uniform hardness, distortion, or cracking. Dies needing lots of electrical discharge machining (EDM) benefit too. Pre-hardened material allows complete cavity production without post-hardening operations.
Key Performance Properties
Customized heat treatment unlocks SKD61’s full performance potential:
Mechanical Properties (Heat Treatment Dependent)
– Yield strength: 1000–1380 MPa depending on hardness level
– Hardness range: 255 HB (annealed) to 52 HRC (hardened and tempered)
– Impact toughness: Changes based on tempering temperature (beats other hot-work tool steels)
Thermal Properties
– Thermal conductivity: ~25–30 W/m·K at room temperature
– Coefficient of thermal expansion: ~10.4 ×10⁻⁶/°C (20–100°C range)
– Elevated temperature strength: Maintains hardness to about 500–550°C
Charpy Impact Toughness Characteristics
– Changes a lot with notch configuration and tempering conditions
– Well-tempered SKD61 shows excellent toughness compared to other hot-work steels
– Multiple tempering cycles boost toughness while maintaining hardness
You can optimize these properties through customized heat treatment protocols. Dies subjected to thermal cycling benefit from stress-relief tempering cycles. This boosts dimensional stability. Impact-loaded forging dies need tempering temperatures optimized for maximum toughness at working hardness.
6. Precision Ground Steel Bar Capabilities
Precision ground SKD61 steel bars give you the highest dimensional accuracy and surface quality:
Precision Ground Features
– Customer-specified tolerances tighter than standard h9–h11
– Tolerances down to h6–h7 grade for critical jobs
– Better surface finish (Ra values 0.4–0.8 μm)
– Complete removal of decarburized surface layer
– Minimal finishing needed
Applications Benefiting from Ground Bars
– Ejector pins and core pins needing precise fit
– Slide components in complex die assemblies
– Guide pillars and bushings where dimensional consistency ensures smooth operation
– Jobs where surface defects could start fatigue failure
Precision ground bars remove the variation in turned or rough-machined stock. Making multiple identical tools or replacement components? Ground bars ensure consistent starting dimensions. This cuts setup time and scrap rates in your machining operations.
7. ESR (Electroslag Remelting) Premium Option
For the toughest jobs, ESR-processed SKD61 offers better material quality:
ESR Process Benefits
– Higher purity levels: Big reduction in non-metallic inclusions
– Isotropic properties: More uniform mechanical properties in all directions
– Improved toughness: Better impact resistance and less crack sensitivity
– Better machinability: More predictable cutting behavior and improved surface finish
– Extended tool life: Fewer microstructural defects that start fatigue failures
Critical Applications Suited for ESR Material
– Large aluminum extrusion dies where failure causes expensive downtime
– High-stress forging dies operating at high temperatures
– Dies needing heavy polishing for optical-quality surfaces
– Tools where failure could pose safety risks
The ESR remelting process melts an electrode of regular SKD61 through a slag layer. This refines the steel by removing inclusions and achieving exceptional cleanliness. ESR material costs about 20–30% more than regular steel. But the investment pays off in jobs where tool life and reliability matter most.
8. Specialized Packaging for Extreme Shipping Conditions
Proper packaging protects your customized SKD61 investment during transit and storage:
Standard Protection Methods
– Black paint coating: Applied to all surfaces for basic corrosion protection
– Plastic film wrapping: Moisture barrier for domestic shipping
– Anti-rust oil spraying: Better corrosion protection for marine transport
– Wooden crate packaging: Impact protection for heavy blocks and forgings
Customized Packaging Solutions
– VCI (Volatile Corrosion Inhibitor) packaging for long-term storage
– Moisture-barrier sealed packaging for tropical areas
– Custom crating with internal support structures for odd-shaped forgings
– Export-grade packaging meeting ISPM 15 international standards
Expensive custom blocks or precision ground bars need good packaging protection. Poor packaging can cause surface corrosion, edge damage, or size changes from moisture. Specify the right packaging based on shipping duration, climate, and handling conditions. Your material arrives in perfect condition.
9. Quality Standards Compliance and Certification
Strict quality control ensures customized SKD61 meets or exceeds international standards:
Applicable Quality Standards
– JIS G4404: Japanese Industrial Standard for hot-work tool steels
– ASTM A681: American standard specification for tool steels
– EN ISO 4957: European standard for tool steels
– GB/T 1299: Chinese national standard for tool steels
Available Quality Certificates
– Mill test certificate: Standard 2.1 certification documenting chemical composition and mechanical properties
– EN 10204 3.1: Manufacturer’s inspection certificate validated by authorized inspector
– Third-party inspection: Independent verification by SGS, TÜV, or other accredited agencies
– Ultrasonic testing reports: Internal soundness verification for critical blocks
– Dimensional inspection reports: Certified measurements for precision ground materials
Aerospace, medical, or other regulated industries need third-party certification. This gives independent verification of material conformance. The extra cost of 3.1 certification or third-party inspection (about 2–5% of material value) provides traceability and liability protection. This justifies the investment for critical jobs.
10. Ordering Customized SKD61
Requesting customized SKD61 steel? Clear communication of needs ensures accurate quotation and delivery:
Essential Specification Elements
1. Dimensions: Diameter/thickness, width, length with tolerance needs
2. Quantity: Number of pieces and total weight
3. Surface finish: Hot rolled, annealed, machined, or ground
4. Heat treatment condition: Annealed, hardened and tempered, or customer heat treatment
5. Standard: JIS, ASTM, DIN, GB, or other applicable specification
6. Quality certification: Mill certificate, 3.1, or third-party inspection needs
7. Special requirements: ESR processing, ultrasonic testing, specific tolerance zones
8. Delivery location: Domestic or export, port of destination
9. Packaging requirements: Standard or customized for shipping conditions
Complete specification clears up confusion and cuts the quotation-to-delivery cycle time. Experienced SKD61 suppliers can often suggest optimization opportunities. Think standard sizes needing minimal lead time. Or alternative finishing methods that cut total cost while meeting functional needs.
Customized SKD61 steel solutions transform material procurement from a commodity transaction into a strategic partnership. Match dimensions, tolerances, surface finish, composition, heat treatment, and quality verification to your specific needs. Customization removes waste, cuts processing costs, and optimizes tool performance for your unique manufacturing environment.