AISI Type S21904 (Alloy 21-6-9) Stainless Steel, sheet and strip 30% cold reduction, tested at RT, stress relieved at 480°C (900°F) for 1 hour

Subcategory: Ferrous Metal; Heat Resisting; Metal; Stainless Steel; T S20000 Series Stainless Steel

Close Analogs: AISI Type S21900

Key Words: UNS S21904, AMS 5595, AMS 5656, ASME SA412, ASTM A269 (XM-11), ASTM A276 (XM-11), ASTM A314 (XM-11), ASTM A412 (XM-11), ASTM A473 (XM-11), ASTM A580 (XM-11)

Component    Wt. % C Max 0.04   Cr 20   Fe 64

Component    Wt. % Mn 9   N 0.23   Ni 6

Component    Wt. % P Max 0.06   S Max 0.03   Si Max 1

Material Notes:
Austenitic, high strength, excellent corrosion resistance, and low magnetic permeability. Applications include aircraft applications such as ducting and bellows systems, tail pipes and exhaust systems, clamps, fasteners, flanges, and hydraulic tubing.

Physical Properties	Metric	English	Comments
Density	7.83 g/cc	0.283 lb/in³
Mechanical Properties
Hardness, Brinell	389	389	Converted from Rockwell C hardness.
Hardness, Knoop	426	426	Converted from Rockwell C hardness.
Hardness, Rockwell C	42	42
Hardness, Vickers	410	410	Converted from Rockwell C hardness.
Tensile Strength, Ultimate	1278 MPa	185000 psi
Tensile Strength, Yield	1229 MPa	178000 psi	at 0.2% offset
Elongation at Break	11 %	11 %	in 50 mm
Modulus of Elasticity	200 GPa	29000 ksi	Typical for stainless steel
Machinability	30 %	30 %	Based on 100% machinability for AISI 1212 steel.
Electrical Properties
Electrical Resistivity	7.3e-005 ohm-cm	7.3e-005 ohm-cm
Thermal Properties
CTE, linear 20°C	16.7 µm/m-°C	9.28 µin/in-°F	at 25-95°C, 17.3 µm/m°C at 25-205°C. Annealed
CTE, linear 250°C	18.2 µm/m-°C	10.1 µin/in-°F	at 25-315°C. Annealed
CTE, linear 500°C	19.1 µm/m-°C	10.6 µin/in-°F	at 25-540°C, 20.0 µm/m-°C at 25-760°C, 20.0 µm/m-°C at 25-870°C, 20.5 µm/m-°C at 25-980°C. Annealed
Specific Heat Capacity	0.48 J/g-°C	0.115 BTU/lb-°F	Typical value for stainless steel.
Thermal Conductivity	13.8 W/m-K	95.8 BTU-in/hr-ft²-°F	13.8 at 95°C, 7.8 W/m°C at -180°C, 10.9 W/m°C at -73°C, 16.1 W/m°C at 205°C, 18.2 W/m°C at 315°C, 20.2 W/m°C at 425°C, 22.5 W/m°C at 540°C, 24.7 W/m°C at 650°C, 26.8 W/m°C at 760°C, 28.9 W/m°C at 870°C

References for this datasheet.