Hot Work Tool Steel Grades for Bulk Supply
Aobo Steel supplies hot work tool steel grades for die casting, hot extrusion, hot forging, hot shear blades, punches, inserts, and high-temperature forming tools. This catalog helps buyers compare H10, H11, H13, H21, L6, and related GB hot work tool steels by application, failure mode, equivalent grade, and bulk supply condition. Cross-standard designations for the H13 family are collected in the H13 equivalent grades reference. Dies that run on low-pressure machines are compared separately in the low-pressure die casting die steel selection guide.
Hot Work Tool Steel Grades Supplied by Aobo Steel
Choose the grade according to working temperature, thermal fatigue, hot wear, impact load, die size, and tooling cost. If the application is not clear, use the selection filter below as a quick starting point.
This filter is for preliminary selection. Final grade choice should consider tool size, working material, operating temperature, cooling method, failure mode, target hardness, and heat-treatment condition.
H10 | 1.2365 | SKD7
Chromium hot work steel for extrusion dies, hot shear blades, and die casting tools requiring toughness, hardenability, and resistance to thermal fatigue.
H11 | 1.2343 | SKD6
Hot work steel with strong toughness and thermal shock resistance for tools exposed to repeated heating, cooling, impact loading, and cracking risk. Its property profile is broken down in the H11 properties and performance guide.
H13 | 1.2344 | SKD61
Widely used hot work tool steel for die casting, extrusion, and forging applications requiring balanced hot hardness, wear resistance, toughness, and heat checking resistance. The element limits behind those properties are listed on the H13 chemical composition page.
H21 | 1.2581 | SKD5
Tungsten hot work steel for high-temperature tooling where red hardness, resistance to softening, and hot wear resistance are more important than maximum toughness.
L6 | 1.2714 | SKT4
Tough forging die steel used for heavy-duty tools where impact resistance, deep hardenability, and resistance to breakage are more important than maximum red hardness.
4Cr5MoSiV1
GB hot work steel used for die casting dies, extrusion dies, and hot forming tools requiring balanced hot strength, thermal fatigue resistance, and wear resistance.
4Cr5MoSiV
GB chromium hot work steel for tools requiring toughness, hardenability, and thermal shock resistance under repeated heating and cooling conditions.
5CrNiMo
Forging die steel used for medium and large hot forging dies requiring toughness, impact resistance, and stable service under repeated forging loads.
5CrMnMo
Forging die steel for hot forging dies and forming tools where toughness, hardenability, and cost control are important in medium-duty applications.
Other H-Series Grades
Some hot work tool steel grades are requested for specific applications, regional standards, or project-based requirements. Availability should be checked by grade, size, quantity, and inspection level.
Please contact Aobo Steel with your application, working temperature, tooling size, required standard, and quantity. We can help check a suitable hot work tool steel grade.
Quick Selection Guide for Hot Work Tool Steel
Hot work steel selection should start from the actual tooling failure mode. Heat checking, plastic deformation, impact cracking, and high-temperature wear usually require different material priorities.
| Application or Failure Mode | Recommended Grade | GB Option | Selection Reason |
|---|---|---|---|
| Aluminum die casting inserts | H13 / H11 | 4Cr5MoSiV1 / 4Cr5MoSiV | H13 is commonly selected for balanced heat checking resistance, hot strength, and wear resistance. H11 is safer when thermal shock and cracking are more serious. |
| Hot extrusion dies | H13 / H10 / H21 | 4Cr5MoSiV1 / 4Cr5MoSiV | H13 is the balanced choice. H10 supports toughness and thermal fatigue resistance. H21 is used when red hardness and high-temperature wear resistance are more important. |
| Hot forging dies | H13 / L6 | 5CrNiMo / 5CrMnMo | H13 is selected for heat resistance and hot strength. L6, 5CrNiMo, and 5CrMnMo are used when impact toughness and forging die performance are more important. |
| Hot shear blades | H10 / H13 | 4Cr5MoSiV | These grades offer a practical balance of toughness, hot strength, and resistance to softening during hot cutting conditions. |
| Brass extrusion and severe hot wear | H21 | Project-based GB selection | Tungsten alloying improves red hardness and resistance to softening at high working temperature. The GB alternative should be confirmed by working temperature and wear severity. |
| Thermal shock and cracking risk | H11 | 4Cr5MoSiV | H11 and 4Cr5MoSiV are often selected when the tool experiences repeated rapid heating and cooling or impact loading. |
Hot Work Steel Groups and Selection Limits
Hot work tool steels are usually grouped by their main alloying system. This classification helps compare toughness, red hardness, thermal fatigue resistance, and high-temperature wear performance.
| Group | Typical Grades | Main Strength | Selection Limit |
|---|---|---|---|
| Chromium hot work steels | H10, H11, H13, 4Cr5MoSiV, 4Cr5MoSiV1 | Good balance of toughness, hardenability, hot strength, and thermal fatigue resistance. | May not be enough for the most severe high-temperature wear conditions. |
| Tungsten hot work steels | H21, H25, H26 | Strong red hardness and resistance to softening at high temperature. | Lower toughness than chromium hot work steels, so cracking risk must be considered. |
| Molybdenum hot work steels | H42, H43 | High hot hardness and resistance to elevated-temperature softening. | Heat treatment and surface condition require careful control. |
| Forging die steels | L6, 5CrNiMo, 5CrMnMo | High toughness and hardenability for forging dies and heavy-duty hot work tools. | Selection should be based on forging load, die size, impact level, and required tool life. |
Hot Work Tool Steel Product Links
Use this table as a quick catalog entry. It helps buyers, stockists, and engineers jump directly to the corresponding product page.
| Grade | Equivalent or Category | Typical Application | Product Page |
|---|---|---|---|
| H10 | 1.2365 / SKD7 | Hot extrusion dies, hot shear blades, die casting tools | View H10 |
| H11 | 1.2343 / SKD6 | Hot punches, extrusion tools, die casting dies | View H11 |
| H13 | 1.2344 / SKD61 | Aluminum die casting, extrusion dies, forging dies | View H13 |
| H21 | 1.2581 / SKD5 | Brass extrusion, hot punches, high-temperature dies | View H21 |
| L6 | 1.2714 / SKT4 | Drop forging dies, heavy-duty tools, forming rolls | View L6 |
| 4Cr5MoSiV1 | GB hot work tool steel | Die casting dies, extrusion dies, hot forming tools | View 4Cr5MoSiV1 |
| 4Cr5MoSiV | GB hot work tool steel | Hot punches, extrusion tools, die casting dies | View 4Cr5MoSiV |
| 5CrNiMo | GB forging die steel | Forging dies, hammer forging tools, heavy-duty dies | View 5CrNiMo |
| 5CrMnMo | GB forging die steel | Hot forging dies, forming tools, medium-duty dies | View 5CrMnMo |