JALLOY 1 is a fine grain, high quality steel for jobs where formability is an important consideration or where use of a low carbon steel with good mechanical properties before or after heat treatment are desired. This datasheet provides information on composition, hardness, and tensile properties as well as fracture toughness. It also includes information on heat treating, machining, and joining. Filing Code: SA-3. Producer or source: Jones & Laughlin Steel Corporation. Originally published November 1952, revised November 1957.