Unified Numbering System

tom2005

Alloy numbering systems vary greatly from one alloy group to the next.  To help alleviate this problem the Unified Numbering System (UNS) for metals and alloys was developed.  An outline of the organization of UNS designations is listed below:

  UNS Series   Metal
  A00001 to A99999 Aluminum and aluminum alloys
  C00001 to C99999 Copper and copper alloys
  D00001 to D99999 Specified mechanical property steels
  E00001 to E99999 Rare earth and rare earthlike metals and alloys
  F00001 to F99999  Cast irons
  G00001 to G99999  AISI and SAE carbon and alloy steels (except tool steels)
  H00001 to H99999  AISI and SAE H-steels
  J00001 to J99999  Cast steels (except tool steels)
  K00001 to K99999 Miscellaneous steels and ferrous alloys
  L00001 to L99999 Low-melting metals and alloys
  M00001 to M99999 Miscellaneous nonferrous metals and alloys
  N00001 to N99999 Nickel and nickel alloys
  P00001 to P99999 Precious metals and alloys
  R00001 to R99999 Reactive and refractory metals and alloys
  S00001 to S99999 Heat and corrosion resistant (stainless) steels
  T00001 to T99999 Tool steels, wrought and cast
  W00001 to W99999 Welding filler metals
  Z00001 to Z99999 Zinc and zinc alloys