ALFA I and ALFA II ALLOYS are 13% chromium ferritic stainless steels with 3 and 4% aluminum, respectively. These steels have superior oxidation resistance. Being ferritic they are not hardenable by heat treatment. This datasheet provides information on composition, physical properties, hardness, and tensile properties as well as creep. It also includes information on corrosion resistance as well as heat treating and joining. Filing Code: SS-525. Producer or source: Allegheny Ludlum Corporation.