9Cr18Mo stainless steel equivalent, chemical composition, mechanical properties

9Cr18Mo Stainless Steel

9Cr18Mo steel is a Chinese GB standard martensitic stainless steel, after quenching, it has high hardness and wear resistance, dimensional stability at high temperatures and low temperatures. 9Cr18Mo stainless steel has similar properties and uses to 9Cr18, but has higher heat resistance and tempering resistance after quenching, molybdenum (Mo) can increase the passivation effect of stainless steel.

Note: 9Cr18Mo (old name) = 102Cr17Mo (new name)

Datasheet and specification

The tables below list the 9Cr18Mo datasheet such as chemical composition and mechanical properties, etc.

Chemical Composition of 9Cr18Mo Steel

The following table shows the chemical composition of 9Cr18Mo (102Cr17Mo) steel.

Notes: The value in parentheses is the maximum value that can be added or allowed.

Mechanical Properties of 102Cr17Mo Steel

• Rockwell material hardness: ≥55 HRC (quenching and tempering)
• Material Brinell hardness: ≤269 HBW (steel bar after annealing)

Physical properties

• Density (g/cm3): 7.70
• Specific heat capacity (J/Kg·K): 430 at 0-100°C
• Thermal conductivity (W/m·K): 16.0 at 100°C
• Linear thermal expansion coefficients (10 ^-6 /K):
  • 10.4 (0-100°C)
  • 11.6 (0-500°C)
• Electrical Resistivity (μΩ·m): 0.80 at 20℃
• Longitudinal modulus of elasticity (kN/mm2): 215 to 20°C
• Magnetic: Yes

Typical heat treatment

• Steel bar annealing temperature: 800-900°C (slow cooling)
• Sample quenching temperature: 1000-1050°C (oil cooling)
• Sample quenching temperature: 200-300°C (air cooling)

Forms

9Cr18Mo steel is mainly used to manufacture parts in friction and corrosive media, such as mechanical cutting tools, cutting tools, knives, surgical blades, bearing rings and balls, valve parts, nozzles, measuring tools and other parts of high wear resistance.

Equivalence

9Cr18Mo steel equivalent to US ASTM, ISO, European EN (Germany DIN, UK BSI) and Japanese JIS standard for reference.