Need a tough tool steel that won’t shatter under impact? Our S7 tool steel delivers exceptional shock resistance with straightforward heat treatment and reliable machining. Stocked in decarb‑free* plate and round bar, it’s a go‑to for many tool and die applications. Contact our expert team to learn more, or shop today.
What is S7 Tool Steel?
S7 tool steel is a shock-resistant grade containing high impact properties. As an air-hardening grade, S7 is stable for heat treatment, and its combination of high machinability and dimensional stability makes it ideal for a variety of different tool and die work.
Chemical Composition
|
Element |
Percent (%) |
|
Chromium |
3.25 |
|
Molybdenum |
1.40 |
|
Silicon |
0.25 |
|
Manganese |
0.70 |
Common Applications for S7 Tool Steel
- Chisels
- Punches
- Moil Points
- Gripper Dies
- Riveting Dies
- Hot Headers
S7 tool steel is recommended for applications that require a high level of shock resistance, medium hot-work properties, and/or ease of machining. Short-run dies used in cold-forming, blanking, and bending also use S7.
Heat Treatment
This is the process of heating metal to an elevated temperature to obtain a change in properties of the metallurgical structure. The heat treatment for S7 is as follows:
- Forging: 1800-2100°F
- Annealing: 1500-1600°F
- Hardening: 1725-1850°F
- Tempering: 400-1150°F
How do you Temper S7 Tool Steel?
Temper S7 for 1 ½ - 2 hours for each inch of the greatest cross-section. Base your tempering temperature on the end use of the metal: 400°F for cold-working and similar applications, and 900°-1000°F for hot-work applications. Tempering at temperatures less than 400°F is not recommended.
S7 Tool Steel Hardness
Hardness tests determine the various properties of a specific metal, which includes its resistance to wear, toughness, and formability. Two widely used tests are Rockwell C and Brinell. Rockwell C is measured in the unit HRC, which is the measurement used below.
|
Tempering Temperature (°F) |
Hardness (HRC) |
|
950°F |
55-56 HRC |
|
1000°F |
54-55 HRC |
|
1050°F |
51-53 HRC |
|
1100°F |
44-46 HRC |
|
1150°F |
38-40 HRC |
Order S7 Tool Steel Today
Ready to spec S7 tool steel? We stock multiple sizes and can coordinate cutting, grinding, and heat treatment to your needs. Check live pricing and availability or request a quote today.