H13 Tool Steel is chromium hot work tool steels which are widely used in hot and cold work tooling applications. H13 tool steel is classified as group H steels by the AISI classification system. This series of steels start from H1 to H19.
AISI H-13 tool steel is characterized by:
- Good resistance to abrasion at both low and high temperatures
- High level of toughness and ductility
- Uniform and high level of machinability and polishability
- Good high-temperature strength and resistance to thermal fatigue
- Excellent through-hardening properties
- Very limited distortion during hardening
In steel H13, the molybdenum and vanadium act as strengthening agents. The chromium content assists die steel H-13 to resist softening when used at high temperatures. H-13 die steels offers an excellent combination of shock and abrasion resistance, and possesses good red hardness. It is capable of withstanding rapid cooling and resists premature heat checking. Tool Steel H13 has good machinability, good weldability, good ductility, and can be formed by conventional means.
Due to H13 tool steel excellent combination of high toughness and fatigue resistance, AISI H13 hot work tool steel is used more than any other tool steel in tooling applications.
Supply Range for AISI H13 Tool Steel
H13 Steel Round Bar: diameter 8mm – 400mm
H13 Steel Plate: thickness 16mm –500mm x width 200mm – 800mm
H13 Steel Slab: 200mm x 500-800mm
Surface Finish: Black, Rough Machined, Turned or as per given requirements.
2. Common H13 Tool Steel Related Specifications
| Country | USA | German | Japan |
| Standard | ASTM A681 | DIN EN ISO 4957 | JIS G4404 |
| Grades | H13 | 1.2344/X40CrMoV5-1 | SKD61 |
3. H13 Tool Steel Chemical Composition
| ASTM A681 | C | Mn | P | S | Si | Cr | V | Mo | ||||||
| H13 | 0.32 | 0.45 | 0.2 | 0.6 | 0.03 | 0.03 | 0.8 | 1.25 | 4.75 | 5.5 | 0.8 | 1.2 | 1.1 | 1.75 |
| DIN ISO 4957 | C | Mn | P | S | Si | Cr | V | Mo | ||||||
| 1.2344 /X40CrMoV5-1 | 0.35 | 0.42 | 0.25 | 0.5 | 0.03 | 0.02 | 0.8 | 1.2 | 4.8 | 5.5 | 0.85 | 1.15 | 1.1 | 1.5 |
| JIS G4404 | C | Mn | P | S | Si | Cr | V | Mo | ||||||
| SKD61 | 0.35 | 0.42 | 0.25 | 0.5 | 0.03 | 0.02 | 0.8 | 1.2 | 4.8 | 5.5 | 0.8 | 1.15 | 1.0 | 1.5 |
4. AISI H13 Steel Mechanical Properties
| Properties | Metric | Imperial |
| Tensile strength, ultimate (@20°C/68°F, varies with heat treatment) | 1200 – 1590 MPa | 174000 – 231000 psi |
| Tensile strength, yield (@20°C/68°F, varies with heat treatment) | 1000 – 1380 MPa | 145000 – 200000 psi |
| Reduction of area (@20°C/68°F) | 50.00% | 50.00% |
| Modulus of elasticity (@20°C/68°F) | 215 GPa | 31200 ksi |
| Poisson’s ratio | 0.27-0.30 | 0.27-0.30 |
5. Forging of H13 Tool Steel Heating for forging must be done slowly and uniformly. Soak through at 1900°-2000°F and reheat as often as necessary, stopping work when the temperature drops below 1650°F. After forging, cool slowly in lime, mica, dry ashes or furnace. H-13 should always be annealed after forging.
6. Heat Treatment for H13 Tool Steels
Heat slowly to 1550°-1650°F, hold until entire mass is heated through, and cool slowly in the furnace (40F per hour) to about 1000°F, after which cooling rate may be increased. Suitable precautions must be taken to prevent excessive carburization or decarburization.
- Stress Relieving
When desirable to relieve the strains of machining, heat slowly to 1050°-1250°F, allow to equalize, and then cool in still air (Strain Relieving). Â
- Preheat Prior to Hardening
Warm slightly before charging into the preheat furnace, which should be operating at 1400°-1500°F.
- Hardening
H13 tool steel is a steel having very high hardenability and should be hardened by cooling in still air. The use of a salt bath or controlled atmosphere furnace is desirable to minimize decarburization, and if not available, pack hardening in spent pitch coke is suggested. The temperature employed is usually 1800°-1850°F, depending on size section.
- Quenching
Quench in still air or dry air blast. If complicated forms are to be hardened, an interrupted oil quench can be used. Quench part in oil and remove from bath when it just loses its color (1000°-1100°F). Finish cooling to below 150°-125°F in air, then temper immediately.
- Tempering
Tempering practice may vary with size and application, but is usually performed in the range of maximum secondary hardness or higher. Double tempering is recommended. The results below is H13 that was air quenched from 1800°F and tempered for 4 hours at various temperatures. The results may be used as a guide, keeping in mind that parts of heavy section or mass may be several points lower in hardness.
7. Application of AISI H13 Tool Steel
- As Tools for Extrusion
| Part | Aluminium, magnesium alloys, HRC | Copper alloys HRC | Stainless steel HRC |
| Dies, Backers, die-holders, liners, dummy blocks, stems | 44-50 | 43-47 | 45-50 |
| 41-50 | 40-48 | 40-48 | |
| Austenitizing temperature | 1,870-1,885°F | 1,900-1,920°F | |
| (1,020-1,030°C) | (1,040-1,050°C) | ||
- As Plastic Molding Tool Steel
| Part | Austenitizing temp. | HRC |
| Injection molds Compression/ transfer molds | 1,870-1,885°F (1,020-1,030°C) | 50-52 |
| Tempering 480°F (250°C) |
- Other Applications
| Applications | Austenitizing temp | HRC |
| Severe cold punching, scrap shears | 1,870-1,885°F | 50-52 |
| (1,020-1,030°C) | ||
| Tempering 480°F (250°C) | ||
| Hot shearing | 1,870-1,885°F | |
| (1,020-1,030°C) | 50-52 | |
| Tempering 480°F (250°C) or | ||
| 1,070-1,110°F | 45-50 | |
| (575-600°C) | ||
| Shrink rings (e.g. for cemented carbide dies) | 1,870-1,885°F | 45-50 |
| (1,020-1,030°C) | ||
| Tempering 1,070-1,110°F | ||
| (575–600°C) | ||
| Wear-resisting parts | 1,870-1,885°F | Core 50-52 Surface ~1000HV1 |
| (1,020-1,030°C) | ||
| Tempering 1,070°F (575°C) | ||
| nitrided |