Type 309 (UNS S30900)

Description

Type 309 is a high temperature chromium nickel austenitic stainless steel that resists oxidation at temperatures up to 1900˚F in dry air at constant temperature. Under thermal cycling conditions this grade resists oxidation up to a temperature of approximately 1850˚F. Type 309 has good sulfidation resistance but low resistance to carburization and should not be used in highly carburizing atmospheres. Type 309 is non-magnetic in the annealed and cold worked conditions and is as resistant to corrosion as Type 304/304L.

Chemical Composition
Chemical Composition (wt%) limits as specified in ASTM A167*
Element 309
Carbon 0.20
Chromium 22.0-24.0
Nickel 12.0-15.0
Manganese 2.00
Silicon 0.75
Phosphorus 0.045
Sulfur 0.030
* Maximum, unless range is indicated
Mechanical Properties
Mechanical property requirements for annealed product as specified in ASTM A167.
Property 309
Yield Strength, min. (ksi) 30
Tensile Strength, min. (ksi) 75
Elongation, min. (%) 40
Hardness, max. (Rb) 95
Physical Properties
Physical properties for Type 309 stainless steel
Property 309
Density, lb/in3 0.285
Modulus of Elasticity, psi 29.0 x 106
Coefficient of Thermal Expansion, 68-212˚F, /˚F 8.7 x 10-6
Thermal Conductivity, Btu/ft hr ˚F 9.0
Specific Heat, Btu/lb ˚F 0.12
Electrical Resistivity, Microohm-in 30.7
Standards
Typical standards for Type 309 stainless steel
Property 309
Density, lb/in3 0.285
Modulus of Elasticity, psi 29.0 x 106
Coefficient of Thermal Expansion, 68-212˚F, /˚F 8.7 x 10-6
Thermal Conductivity, Btu/ft hr ˚F 9.0
Specific Heat, Btu/lb ˚F 0.12
Electrical Resistivity, Microohm-in 30.7

Data are typical, are provided for informational purposes, and should not be construed as maximum or minimum values for specification or for final design, or for a particular use or application. The data may be revised anytime without notice. We make no representation or warranty as to its accuracy and assume no duty to update. Actual data on any particular product or material may vary from those shown herein.  © 2014 RMP Inc. All rights reserved.