Type 439 (UNS S43035)

Description
Type 439 is an 18% chromium, titanium stabilized ferritic stainless steel with corrosion resistance similar to that of 304/304L stainless steel.  This grade may be used in the annealed, cold formed or as-welded condition in applications where other stainless steels such as Type 304/304L and Type 430 are used.  Type 439 has good weldability due to titanium stabilization and has excellent resistance to stress corrosion cracking.  Type 439 outperforms Type 409 in both oxidation and corrosion resistance and typical applications include tubular manifolds and exhaust system components.

Chemical Composition
Chemical Composition (wt%) limits as specified in ASTM A240 and ASME SA240*
Element 439
Carbon 0.030
Chromium 17.0-19.0
Nickel 0.50
Manganese 1.00
Silicon 1.00
Nitrogen 0.030
Phosphorus 0.040
Sulfur 0.030
Aluminum

0.15

Titanium

0.20 +4(C+N) min
1.10 max

* Maximum, unless range is indicated
Mechanical Properties
Mechanical property requirements for annealed product as specified in ASTM A240 and ASME SA240
Property 439
Yield Strength, min. (ksi) 30
Tensile Strength, min. (ksi) 60
Elongation, min. (%) 22
Hardness, max. (Rb) 89
Physical Properties
Physical properties for Type 439 stainless steel
Property 439
Density, lb/in3 0.278
Modulus of Elasticity, psi 29.0 x 106
Coefficient of Thermal Expansion, 68-212˚F, /˚F 5.6 x 10-6
Thermal Conductivity, Btu/ft hr ˚F 14.0
Specific Heat, Btu/lb ˚F 0.11
Electrical Resistivity, Microohm-in 24.8

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.