H12 Round Bar – High-Performance Hot Work Tool Steel for Die & Mold Applications
H12 Round Bar is a premium-grade hot work tool steel widely used in applications where tools are exposed to high temperatures, heavy impact loads, and continuous thermal stress. Known for its excellent hot hardness, toughness, and wear resistance, H12 steel is a preferred material for die casting, forging, extrusion, and hot forming tools.
When buyers search for H12 Die Steel Round Bar or ASTM/AISI H12 tool steel, they are usually looking for a material that can resist cracking, deformation, and early tool failure. From practical industry experience, we know that H12 delivers consistent performance in demanding environments where ordinary steels fail.
What is H12 Tool Steel?
AISI H12 tool steel belongs to the chromium-based hot work tool steel family. It is designed to maintain strength and hardness even when exposed to elevated operating temperatures, making it ideal for hot dies and tooling components.
Key characteristics of H12 Die Steel include:
- High resistance to thermal fatigue
- Excellent toughness and impact strength
- Good wear resistance at high temperatures
- Reliable dimensional stability after heat treatment
H12 Tool Steel Round Bar – Hot Rolled, Smooth Finish is commonly used where durability and long service life are essential.
Standards & Equivalent Grades of H12 Die Steel
H12 tool steel is recognised globally under multiple standards:
- ASTM / AISI H12
- DIN 1.2605
- X35CrWMoV5
- SKD62
- ASTM H12 Tool Steel 1.2605 X35CrWMoV5 SKD62 Alloy Steel Tool Steel Die Steel Round Bar
In industrial practice, H12 is often compared with or selected alongside grades such as:
- W.Nr. 55NiCrMoV6 Hot Die Steel Bars
- 1.2713 Bar
- 55NiCrMoV6
- DIN 1.2714 Hot Die Steel 2714 Flat Bars
Heat Treatment Characteristics
ASTM H12 Tool Steel responds very well to heat treatment, which allows manufacturers to tailor properties based on application needs.
Common heat treatment processes include:
- Annealing: Improves machinability
- Hardening: Achieves high strength and wear resistance
- Tempering: Balances hardness with toughness
Proper heat treatment significantly increases the service life of H12 Die Steel Round Bars.
H12 Tool Steel Round Bar – Specifications Table
| Parameter | Details |
| Product Name | H12 Round Bar |
| Steel Grade | ASTM / AISI H12 |
| Material Type | Hot Work Tool Steel |
| Other Designations | DIN 1.2605, X35CrWMoV5, SKD62 |
| Form Supplied | Round Bar |
| Manufacturing Process | Hot Rolled |
| Surface Finish | Black / Smooth Finish |
| Diameter Range | 10 mm to 600 mm |
| Length | Random / Cut Length |
| Heat Treatment Condition | Annealed / Hardened & Tempered |
| Application | Die Casting, Forging, Extrusion, Hot Work Tools |
Chemical Composition Table – ASTM/AISI H12 Tool Steel
| Element | Percentage (%) |
| Carbon (C) | 0.32 – 0.45 |
| Chromium (Cr) | 4.75 – 5.50 |
| Tungsten (W) | 1.00 – 1.50 |
| Molybdenum (Mo) | 1.25 – 1.75 |
| Vanadium (V) | 0.80 – 1.20 |
| Silicon (Si) | 0.80 – 1.20 |
| Manganese (Mn) | 0.20 – 0.50 |
| Phosphorus (P) | ≤ 0.030 |
| Sulfur (S) | ≤ 0.030 |
Mechanical Properties Table – H12 Round Die Steel Bars
| Property | Typical Value |
| Tensile Strength | 1,550 – 1,900 MPa |
| Yield Strength | ≥ 1,300 MPa |
| Elongation | 10–14% |
| Impact Toughness | High |
| Hardness (Annealed) | 200 – 235 HB |
| Hardness (Hardened & Tempered) | 48 – 52 HRC |
| Modulus of Elasticity | ~210 GPa |
Applications of H12 Round Bar
Based on real industrial usage, H12 Tool Steel Round Bar is widely used in:
Die Casting
- Aluminum and magnesium die casting dies
- Core pins and ejector pins
- Inserts exposed to molten metal
Forging Industry
- Hot forging dies
- Punches and mandrels
- Press tools
Extrusion & Hot Working
- Extrusion dies
- Hot shear blades
- Hot cutting tools
Mold Making
- Mold inserts
- Structural mold components
Why Choose H12 Die Steel Round Bar?
Compared to other hot work steels like DIN 1.2714 Hot Die Steel 2714 Flat Bars or 55NiCrMoV6, H12 Die Steel offers a better balance of:
- Heat resistance
- Toughness
- Wear resistance
- Cost-effectiveness
This makes H12 Round Die Steel Bars a reliable choice for long-term industrial performance.
H12 Round Bar is a proven hot work tool steel designed for high-temperature and high-stress applications. With international equivalents like DIN 1.2605, X35CrWMoV5, SKD62, and compatibility with grades such as 1.2713 Bar and DIN 1.2714 Hot Die Steel, H12 remains a trusted material across industries.
If you are looking for durable, heat-resistant H12 Die Steel Round Bars backed by real-world application knowledge and strict quality standards, we are ready to support your requirements.
Global Reach
ASC LLP boasts a robust global presence, committed to delivering unparalleled service and quality to clients around the world. Our dedication to prompt delivery and exceptional customer care sets us apart in the industry. Major corporations across the USA, Europe, Asia, and other regions place their trust in our high-quality H13 Tool Steel Bars. This widespread trust underscores our reputation for reliability and excellence. By consistently meeting and exceeding the expectations of our international clientele, we continue to solidify our position as a leader in the global steel market.
Countries We Export To
UNITED STATES, EUROPE, UK, UAE, SAUDI ARABIA, OMAN, KUWAIT, JORDAN, QATAR, INDONESIA, MALAYSIA, BRAZIL, SPAIN, ITALY, FRANCE, GERMANY, BAHRAIN, SRI LANKA, AZERBAIJAN, AUSTRALIA, AUSTRIA, PHILIPPINES, TURKEY, RUSSIA, IRAN, IRAQ, CANADA, KOREA, JAPAN, YEMEN, FINLAND, ZIMBABWE, HUNGARY, PORTUGAL, VIETNAM, MOROCCO, THAILAND, SOUTH AFRICA, MEXICO, SINGAPORE, GREECE, KUWAIT, POLAND, NEW ZEALAND, SWEDEN, SWITZERLAND, BELGIUM, BHUTAN, BANGLADESH, TAIWAN, ROMANIA, CAMBODIA, KAZAKHSTAN, AFGHANISTAN.
