S1 / DIN 1.2550 / AISI S1 Steel Grade

Toolman Special Steels is proud to produce and offer S1(1.2550) - AISI S1 is an impact resistant tool steel with extremely high toughness, and high hardenability. It can be used for tungsten alloy cold work tools. It is applied for cutting tools for plates, wood-working tool, and blanking dies.

Steel Properties
  • High impact resistance

  • Good wear resistance

  • Good toughness with high strength

  • High hardenability

  • Shock resisting tool steel with very good toughness in combination with high hardenability.

Chemical Composition

C Si Mn P S Cr Mo V W
0.40 - 0.55 0.15 - 1.20 0.10- 0.40 0.03 0.03 1.00- 1.80 0.00 - 0.50 0.15 - 0.30 1.50 - 3.00

Mechanical Properties

Property Value
Annealing Hardness (HBW) 229 max
Quenching and Tempering Hardness (HRC) 56 min

Physical Properties

Property Value
Density (g/cm³) 7.86

Modulus of Elasticity

Temperature (°C) GPa
20 190

Thermal Properties

Temperature (℃) Thermal Expansion Coefficient (10^-6/℃)
20 -100 12.4

Thermal Conductivity

Temperature (℃) Thermal Conductivity (W/m•K)
20 41

HEAT TREATMENT AND PROCESSES

Heat treatment

Heat Treatment Temperature Duration Cooling
Stress Relieving Approx. 650 °C in the annealed state 1 hour per 50 mm wall thickness Furnace
Soft Annealing 760 °C 1 hour per 25 mm wall thickness Furnace
Hardening 890 °C 1 minute per mm wall thickness -
Quenching Hardness Max. 64 HRC - in oil, hot bath or vacuum
Tempering See tempering curve 1 hour per 25 mm wall thickness Air
Working Hardness 58–62 HRC - -
Tempering °C after Quenching HRC
100 60
200 58
300 56
400 52
500 48
600 43
Applications
  • Blanking dies for cutting sheets up to 12 mm thickness

  • Trimming and splitting dies

  • Cold piercing punches

  • Preforming punches

  • Shear blades

  • Chipping knives

  • • Pneumatic chisels

  • Coining tools,

  • Cold shear blades

  • Ejectors

Quality Assurance

Our S1 1.2550 steel undergoes rigorous testing and quality control to meet international standards, ensuring consistent performance and reliability. Certificates and test reports are available upon request. Feel free to reach out to us for more information on our S1 1.2550 steel products or to discuss your specific requirements. We're dedicated to providing top-quality steel solutions that meet your needs and exceed your expectations.

Manufacturing Range

Products Diameter (mm)
Hot Rolled bar 8 - 65
Forged and Turned bars 65.2 - 500
Forged Square Bars 50 - 500

Flats

THICKNESS WIDTH
6.00 mm - 410.00 mm 20.00 mm - 700.00 mm