US number

The US number ( English abbreviation for U nified N umbering S ystem for Metals and Alloys ) is a system in which each metal is determined with a letter and five digits. It is an industrial system from which no special properties or exact compositions with defined limit values can be derived.

However, other designations can sometimes be found in the UNS system, for example aluminum EN AW-6061 according to EN 573-3 corresponds to UNS A96061.

US system

• Axxxxx - aluminum - alloy
• Cxxxxx - copper alloys, including bronze
• Fxxxxx - ferrous materials
• Gxxxxx - carbon steels
• Hxxxxx - stainless steels ( AISI H)
• Jxxxxx - cast steels
• Kxxxxx - high strength steels
• L5xxxx - lead alloys, incl. Bearing metals and hard solders
• M1xxxx magnesium alloys
• Nxxxxx - nickel alloys
• Rxxxxx - refractory alloys
  • R03xxx- molybdenum
  • R04xxx- niobium
  • R05xxx- tantalum
  • R3xxxx- cobalt
  • R5xxxx- titanium
  • R6xxxx- zirconium
• Sxxxxx - stainless steels, including chromium - nickel steels
• Txxxxx - tool steels
• Zxxxxx - zinc alloys

Web links

• Online material database (English)