AK Steel 439 LT is a ferritic stainless steel that has both oxidation resistance and corrosion resistance superior to Type 409, making the alloy attractive for numerous difficult-to-form automotive exhaust applications. The lower titanium content of this alloy compared to Type 439 (see Alloy Digest SS-874, February 2003) provides an improved surface essentially free from titanium scale. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as deformation. It also includes information on corrosion resistance as well as forming and joining. Filing Code: SS-880. Producer or source: AK Steel Corporation.