S7 Steel: Unmatched Reliability for Demanding Applications
S7 steel provides exceptional shock resistance, dimensional stability, and versatility to meet the most demanding requirements.
Get Superior S7 material from Aobo Steel at Competitive Prices
S7 steel is an American ASTM standard S7 heavy-duty and medium-carbon alloy tool steel. Its high chromium content offers good tempering resistance and resistance to high-temperature oxidation.
Aobo Steel is a professional supplier, providing over 20 types of steel in the tool steel product sector. We are not just a material supplier but also a service supplier.. Our top-quality technology and customer service enable small and medium-sized factories worldwide to conveniently obtain reliable quality material at the best price.
Additional information: When looking for an S7 material equivalent, 1.2355 is often considered a close match.
Application Scenarios



- Cold Work Tools: Includes shear blades, punches, chisels, swaging dies, and gripper dies, all needing high impact resistance.
- Molding Applications: Used in plastic injection molds and inserts, ensuring precision and durability.
- Die Casting: Suitable for aluminum and zinc casting dies, offering good thermal fatigue resistance.
- Hot Work Tools: Applied in environments up to 1000°F, such as forging dies and aerospace components.
Why choose Aobo Steel as your supplier
We offer over 100 types of steel, including tool steel, alloy steel, stainless steel, alloy structural steel, and carbon steel.
We provide free cutting services.
With over 40 processing suppliers surrounding us, we have the capacity to deliver more than 2,000 tons of steel per month.
S7 tool steel Properties
What is S7 steel? Here we understand it from data, including composition, properties, heat treatment, etc.
S7 Steel Composition
Elemento | Carbono (C) | Manganês (Mn) | Silício (Si) | Cromo (Cr) | Molibdênio (Mo) |
Content (%) | 0.45-0.55 | 0.20-0.80 | 0.20-1.00 | 3.00-3.50 | 1.30-1.80 |
Heat treatment
- Annealing Specification: For the best softening effect, the annealing temperature is 810–830°C, and the cooling rate is 15–30°C/h.
- Quenching and Tempering Specification: The quenching temperature is 850–880°C, and the tempering temperature is 550°C.
Physical property
Propriedade | Valor |
---|---|
Hardness (after heat treatment) | 55-60 HRC |
Tensile Strength (UTS) | 670-2030 MPa (97-290 x 10^3 psi) |
Módulo elástico | 190 GPa (28 x 10^6 psi) |
Poisson’s Ratio | 0.29 |
Shear Modulus | 74 GPa (11 x 10^6 psi) |
Impact Strength (Charpy V-notch) | 10-12.5 ft-lb (13.6-16.9 J at various temperatures) |
The benefits
Exceptional Shock Resistance and Impact Toughness
Air-Hardening Capability with Minimal Distortion
Easy Machinability in Annealed Condition
Good Dimensional Stability
Adequate Wear Resistance
Resistance to Thermal Fatigue in Hot Work Conditions
S7 tool steel vs. other steels
In production practice, S7 and 4140 steel are always difficult to choose; S7 is a hot work tool steel, and 4140 is a low alloy steel. We compare their data to give users a reference. S7 tool steel vs 4140:
Propriedade | S7 Tool Steel | 4140 Steel |
---|---|---|
Type | Shock-resisting tool steel | Chromium-molybdenum alloy steel |
Composition | C: 0.50%, Cr: 3.25%, Mo: 1.10%, V: 0.30% | C: 0.40%, Cr: 0.95%, Mo: 0.20% |
Dureza (HRC) | 55-60 | 50-55 |
Strength | High (tensile strength ~240 KSI) | High (tensile strength ~140-160 KSI) |
Toughness | Excellent (high impact resistance) | Good |
Wear Resistance | Good | Good |
Heat Resistance | Good (up to 1000°F) | Fair (up to 600°F) |
Machinability | Good (in annealed condition) | Good (in annealed condition) |
Cost | Higher | Lower |
Typical Uses | Punches, dies, shear blades | Gears, shafts, structural parts |
Take the Next Step Toward Better Performance
Don’t wait for another material failure to halt your progress. S7 steel offers the strength, reliability, and versatility your manufacturing projects demand.
The AISI S7 Equivalent: DIN 1.2355
In the German steel standard, S7 steel is equivalent to DIN 1.2355. They have similar chemical compositions and mechanical properties, and can be substituted for each other.
1.2355 steel Chemical composition
Carbono (C) | Cromo (Cr) | Molibdênio (Mo) | Vanádio (V) | Manganês (Mn) | Silício (Si) | Fósforo (P) | Enxofre (S) |
0.45 – 0.55 | 3.00 – 3.50 | 1.30 – 1.70 | 0.15 – 0.35 | 0.50 – 0.90 | 0.20 – 0.80 | max 0.030 | max 0.020 |
1.2355 tool steel Physical Property
Physical Property | Valor | Units | Notes |
---|---|---|---|
Densidade | 7.76 | g/cm³ | Approximate value. |
Coefficient of Thermal Expansion (CTE) | 12.6 | μm/m·K (20-200 °C) | Varies with temperature. |
Coefficient of Thermal Expansion (CTE) | 13.3 | μm/m·K (20-425 °C) | Varies with temperature. |
Coefficient of Thermal Expansion (CTE) | 13.7 | μm/m·K (20-500 °C) | Varies with temperature. |
Modulus of Elasticity | 207 | GPa | Approximate value. |