ASTM A681 H13 EFS Super Fine Hot Work Tool Steel Bar
Short Description:
H13 EFS Super Fine hot work tool steel bar offers refined structure, thermal fatigue resistance and hot strength for die casting dies, extrusion tooling and hot punches. Custom diameter, surface, cutting, UT, MTC and EN 10204 3.1 available.
H13 EFS Super Fine Hot Work Tool Steel Bar is a refined-structure H13 type chromium-molybdenum-vanadium hot work tool steel supplied as round bar or forged bar for die casting dies, extrusion tooling, hot punches, mandrels, hot shear blades and high-temperature forming tools. It is commonly associated with AISI H13, UNS T20813, DIN 1.2344, JIS SKD61 and X40CrMoV5-1, depending on the applicable specification.
SAKY STEEL supplies H13 EFS Super Fine tool steel bar in annealed, forged, peeled, turned or ground condition according to purchase requirements. Available services may include cutting, peeling, turning, grinding, rough machining, dimensional inspection, hardness testing, ultrasonic testing when specified, MTC and EN 10204 3.1 documentation.
Product Parameters
| Item | Product Details |
|---|---|
| Product Name | H13 EFS Super Fine Hot Work Tool Steel Bar |
| Grade | H13 / 1.2344 / SKD61 |
| UNS / EN Designation | UNS T20813 / X40CrMoV5-1 |
| Material Family | Hot work tool steel |
| Product Shape | Round bar and forged bar |
| Size Range | Regular and custom diameters by order |
| Length | 1000–6000 mm or cut to length |
| Surface Finish | Black, peeled, turned, ground |
| Delivery Condition | Annealed or heat treated when specified |
| Standard | ASTM A681 / DIN EN ISO 4957 |
| Tolerance | Mill, h9, h11 or drawing-specific |
| Available Services | Cutting, peeling, turning, grinding, machining |
| Certificates | MTC, EN 10204 3.1, dimensional report |
Chemical Composition
H13 is a chromium-molybdenum-vanadium hot work tool steel. Its alloy balance provides hardenability, hot strength, toughness and resistance to thermal fatigue in hot work tooling. The following values are typical reference ranges; exact limits may vary by standard version and customer specification.
| Element | Typical Reference Content | Technical Function |
|---|---|---|
| Carbon | About 0.32–0.45% | Provides hardenability and working hardness |
| Chromium | About 4.75–5.50% | Improves hardenability and hot work performance |
| Molybdenum | About 1.10–1.75% | Supports temper resistance and hot strength |
| Vanadium | About 0.80–1.20% | Refines grain and improves wear resistance |
| Silicon | About 0.80–1.20% | Supports oxidation resistance and matrix strength |
| Manganese | About 0.20–0.50% | Supports melting control and hardenability |
| Phosphorus | Controlled maximum | Restricted to support toughness |
| Sulfur | Controlled maximum | Restricted to limit inclusions and improve tool reliability |
| Iron | Balance | Base metal matrix |
Actual chemical composition shall be confirmed by the applicable product specification and MTC.
Mechanical and High-Temperature Properties
Mechanical and service properties of H13 EFS Super Fine tool steel bar depend on diameter, melting route, heat treatment, working hardness, test direction and service temperature. The values below are typical references and should not replace order-specific MTC or heat-treatment results.
| Property | Typical Reference | Condition | Engineering Meaning |
|---|---|---|---|
| Annealed Hardness | Usually below about 229 HB | Annealed bar | Improves machinability before hardening |
| Working Hardness | About 44–52 HRC reference | Hardened and tempered | Selected according to die application |
| Thermal Fatigue Resistance | Good for hot work tooling | Repeated heating and cooling | Helps resist heat checking in dies |
| Hot Strength | Good retention after tempering | Application dependent | Useful in die casting and extrusion tooling |
| Toughness | Improved by refined structure | EFS / Super Fine quality when specified | Supports resistance to cracking in critical tools |
| Density | About 7.8 g/cm³ reference | Room temperature | Used for bar weight calculation |
| Hardening Temperature | About 1010–1030°C reference | Subject to heat-treatment practice | Must be controlled by qualified procedure |
| Tempering Range | About 540–620°C reference | After hardening | Adjusts hardness, toughness and heat resistance |
Common Size Table
| Diameter | Length | Surface | Processing | Typical Use |
|---|---|---|---|---|
| Ø10–30 mm | 1000–6000 mm | Peeled or ground | Cutting and grinding | Hot punches and tool pins |
| Ø35–80 mm | 2000–6000 mm | Peeled or turned | Machining allowance | Mandrels and tooling shafts |
| Ø85–160 mm | Custom cut length | Rough turned | Saw cut or machined | Die casting die components |
| Ø165–300 mm | Made to order | Forged and turned | UT when specified | Large hot work tooling |
| Above Ø300 mm | Project specific | Forged or machined | Technical review required | Heavy die blocks and inserts |
Different Specifications Comparison
Round Bar Surface and Production Comparison
| Condition | Main Feature | Recommended Use | Purchase Advice |
|---|---|---|---|
| Hot Rolled Bar | Economical mill surface | Rough machining | Specify machining allowance |
| Forged Bar | Suitable for large sections | Heavy dies and tooling blanks | UT and forging ratio may be specified |
| EFS / Super Fine Bar | Refined structure and improved cleanliness | Critical die casting and extrusion tools | Confirm melting route and inspection level |
| Peeled Bar | Scale-free surface | CNC machining | Reduces surface preparation |
| Ground Bar | Tight tolerance and smooth finish | Precision tooling components | State h9, h8 or drawing tolerance |
Comparison with Related Hot Work Tool Steels
| Grade | Main Strength | Relative Limitation | Typical Selection |
|---|---|---|---|
| H11 / 1.2343 | Good toughness and heat checking resistance | Different alloy balance from H13 | General hot work tools requiring toughness |
| H13 / 1.2344 | Balanced toughness, hot strength and heat checking resistance | Needs controlled heat treatment for best service life | Die casting, extrusion and forging tools |
| H13 ESR / EFS | Improved cleanliness and isotropy when specified | Higher cost than conventional H13 | Critical dies and long-service tooling |
| H21 / 1.2581 | High tungsten red hardness | Different toughness and machinability balance | Special hot punches and hot work tools |
Equivalent Standards and International Names
| System | Designation | Relationship |
|---|---|---|
| AISI / ASTM | H13 | Common hot work tool steel grade |
| UNS | T20813 | UNS designation for H13 type steel |
| DIN / W.Nr. | 1.2344 | German material number reference |
| EN Name | X40CrMoV5-1 | European chemical designation |
| JIS | SKD61 | Japanese cross-reference |
| Chinese Reference | 4Cr5MoSiV1 | Common Chinese hot work tool steel reference |
| Product Standard | ASTM A681 / DIN EN ISO 4957 | Tool steel specification references |
Production Process Flow
Alloying materials are selected according to the required H13 chemistry.
Chemistry, cleanliness and residual elements are controlled during melting.
EFS / Super Fine quality may require agreed refining, cleanliness or structure control.
The material is reduced into round bar or forged bar form.
Annealing improves machinability before final tool manufacturing.
Bars may be peeled, turned, ground or cut to size.
Dimensions, surface, hardness and documentation are checked.
Heat-number marking and export packing are prepared.
Product Inspection
| Inspection | Method | Purpose |
|---|---|---|
| Chemical Analysis | Laboratory analysis or MTC review | Confirm H13 / 1.2344 chemistry |
| PMI | Positive material identification | Available when specified; not a substitute for full chemistry |
| Hardness Test | HB or HRC test as applicable | Confirm annealed or heat-treated condition |
| Dimensional Inspection | Caliper, micrometer and length check | Verify diameter, length and tolerance |
| Surface Inspection | Visual and finish inspection | Check cracks, scale, laps or handling damage |
| Ultrasonic Testing | UT when specified | Evaluate internal soundness in suitable sizes |
| Microstructure Review | Available when specified | Supports EFS / Super Fine quality verification |
| Traceability Review | Heat number and label verification | Link product to MTC and EN 10204 3.1 |
Product Packaging
Bars can be protected with oil, VCI paper, film or waterproof wrapping.
Steel straps, separators and padding reduce movement and scratching.
Ground or machined bars can receive end caps or padded protection.
Export packing is selected according to bar diameter, length and weight.
Grade, size, heat number and customer shipping marks can be retained.
Applications, Core Performance and Fabrication
Primary Applications
- Die casting dies and inserts
- Aluminum extrusion dies and extrusion tooling
- Hot forging dies and die inserts
- Hot punches, mandrels and punch holders
- Hot shear blades and trimming tools
- Plastic molds requiring high polishability and thermal stability, when specified
Core Performance
H13 is widely used because it provides a balanced combination of toughness, hot strength, resistance to thermal fatigue and resistance to softening. EFS / Super Fine quality is especially useful where refined structure and improved cleanliness are requested for critical tooling.
Machinability
Machinability is generally good in the annealed condition. Major turning, milling, drilling and rough machining are usually completed before hardening and tempering. Ground or peeled bars help reduce surface preparation before CNC machining.
Heat Treatment
H13 is normally supplied annealed before machining and then hardened and tempered to the required working hardness. Heat treatment should be selected according to section size, die geometry, target hardness, working temperature and expected impact load.
Welding and Repair
Repair welding may be possible with a qualified procedure, proper preheating, suitable filler metal and post-weld heat treatment. For critical die casting or extrusion dies, repair decisions should consider cracking risk, hardness transition and remaining service life.
Why Choose SAKY STEEL?
Diameter, length, surface finish and machining allowance can be supplied according to drawings.
Material identification can be maintained from documentation to final packing.
MTC (Mill Test Certificate / 质保书) can be provided according to the purchase order.
EN 10204 3.1 documentation is available when specified by the order.
Hardness, dimensional, PMI, UT and microstructure review can be arranged when specified.
Bundles, wooden cases, pallets and customer shipping marks can be arranged.
FAQ
What is H13 EFS Super Fine tool steel?
H13 EFS Super Fine is an H13 hot work tool steel bar supplied with a refined structure or enhanced quality requirement. The exact meaning of EFS should be confirmed by the agreed technical specification, such as melting route, grain size, cleanliness, UT level or microstructure control.
Is H13 the same as DIN 1.2344 and SKD61?
H13 is commonly cross-referenced with DIN 1.2344 and JIS SKD61. However, final equivalence should always be checked by chemical composition, heat-treatment requirement, hardness, inspection criteria and the governing standard.
What standard applies to H13 tool steel bar?
ASTM A681 is commonly referenced for AISI H13 tool steel, while DIN EN ISO 4957 may be used for DIN 1.2344 / X40CrMoV5-1. The purchase order should specify the required standard and revision.
What is the advantage of EFS or Super Fine H13?
EFS or Super Fine H13 is intended to provide a refined structure and improved reliability for demanding hot work tooling. It is especially useful when the tool must resist heat checking, cracking and repeated thermal cycling.
Can H13 EFS bar be supplied ground or peeled?
Yes. Black, peeled, turned and ground surfaces can be discussed according to diameter, tolerance and final machining requirement. Ground bars are suitable where tighter diameter control or improved surface finish is required.
Is ultrasonic testing available for H13 EFS bars?
UT can be arranged for suitable bar diameters and forged bars when specified. The order should define the test method, acceptance level and reporting requirement.
Can MTC and EN 10204 3.1 be provided?
SAKY STEEL can provide MTC and EN 10204 3.1 documentation according to the purchase order. Hardness, dimensional, PMI, UT or microstructure reports may also be arranged when specified.
