THYROTHERM 2344 EFS is an electric arc melted, vacuum degassed hot work tool steel with good resistance to thermal shock and the capability to be polished to lens quality. This datasheet provides information on composition, physical properties, and hardness as well as fracture toughness. It also includes information on heat treating, machining, and surface treatment. Filing Code: TS-524. Producer or source: Thyssen Specialty Steels Inc.