CEN ISO/TR 20173:2009

ISO/TR 20173:2009 provides an American grouping system for materials for welding purposes, classified in accordance with the grouping system of ISO/TR 15608:2005.
It may also apply for other purposes, such as heat treatment, forming, and non-destructive testing. Types of steels are listed in accordance with the grouping system of ISO/TR 15608:2005, Table 1.
ISO/TR 20173:2009 covers grouping systems for the following standardized materials: steel; aluminium and its alloys; nickel and its alloys; copper and its alloys; titanium and its alloys; zirconium and its alloys; and cast irons.