SteelWhat is H13 steel and what is it used for? Hot work tool steel
H13 steel is a hot work tool steel. In this guide we explain what H13 steel is, its chemical composition, hardness, how it is heat treated, what it is used for and the sizes we stock.
What is H13 steel?
Chrome-molybdenum-vanadium hot work tool steel. Combines good toughness with high resistance to shock and thermal fatigue, retaining its hardness at elevated temperatures. For aluminum die-casting dies, forging dies and hot extrusion.
Chemical composition of H13 steel
This is the typical composition of H13 steel (AISI H13 / EN-DIN 1.2344 / JIS SKD61 standard):
| Element | Contents | What for? |
|---|---|---|
| Carbon (C) | 0.32 – 0.45 % | Hardness and wear resistance |
| Silicon (Si) | 0.80 – 1.25 % | Deoxidizer |
| Manganese (Mn) | 0.20 – 0.60 % | Hardenability |
| Chromium (Cr) | 4.75 – 5.50 % | Hardenability and wear resistance |
| Molybdenum (Mo) | 1.10 – 1.75 % | Hot hardness and hardenability |
| Vanadium (V) | 0.80 – 1.20 % | Refines the grain and forms hard carbides |
| Phosphorus (P) | 0.030 % max. | Impurity, kept low |
| Sulfur (S) | 0.030 % max. | Impurity, kept low |
Hardness and heat treatment of H13 steel
The typical working hardness of H13 is 44 – 52 HRC. It is quenched and tempered. It resists thermal fatigue (heating and cooling cycles) and retains its hardness at elevated temperatures, making it the standard for hot work. You can see the full overview in our article on heat treatments for steel, and hardness scales in steel hardness.
What is it for? Applications of H13
H13 steel is mainly used in:
- Die casting molds
- Aluminum extrusion dies
- Hot forging dies
- Hot work punches
- Casting inserts
- Injection sleeves
- Hot shearing blades
- Plastic injection molds
- Hot forming tools
Forms and sizes we carry
At NAT MAC we stock H13 steel in these forms and sizes:
| Package size | Sizes |
|---|---|
| Round bars | Ø 1/4" – 12" (Ø 6 – 305 mm) |
| Plates | 3/8" – 12" (10 – 305 mm) |
If you need a particular size, tell us which one and we will gladly source it for you.
H13 equivalents and standards
H13 steel is also identified by these standards: AISI H13 / EN-DIN 1.2344 / JIS SKD61. You can see how to read them in our article on steel standards.
In summary
- H13 is a hot work tool steel
- Typical composition: C 0.32 – 0.45 and Cr 4.75 – 5.50, plus alloying elements
- Typical working hardness: 44 – 52 HRC
- Ideal for hot work and aluminum die casting
- We carry it in round bar (1/4" – 12") and plates (3/8" – 12"), cut to size
Why buy your H13 steel at NAT MAC?
We have more than 54 years of experience as an industrial supplier and ISO 9001 certified quality. We carry a wide range of tool grade steels and help you choose the right one for your tool or mold.
- Quality H13 Steel, backed and traceable
- Material cut to the size you need
- Technical advice on choosing the right grade
- Wide range of tool-grade steels in stock
- On-time deliveries and competitive prices
Tell us what tool or mold you are going to make and in what dimensions, and we will recommend the right grade and form. Request your free quote.
Sources: data sheet from our NAT MAC catalog (composition, sizes and applications) and public industry references for working hardness. Values are for reference and may vary by standard, heat and treatment.



