Unified numbering system
The unified numbering system (UNS) is an alloy designation system widely accepted in North America. It consists of a prefix letter and five digits designating a material composition. For example, a prefix of S indicates stainless steel alloys, C indicates copper, brass, or bronze alloys, T indicates tool steels, and so on. The first 3 digits often match older 3-digit numbering systems, while the last 2 digits indicate more modern variations. For example, Copper Alloy No. 377 (forging brass) in the original 3-digit system became C37700 in the UNS System. The UNS is managed jointly by the ASTM International and SAE International. A UNS number alone does not constitute a full material specification because it establishes no requirements for material properties, heat treatment, form, or quality.
Some common materials and translations to other standards:
- UNS K11547 is T2 tool steel
- UNS S17400 is ASTM grade 630, Cr-Ni 17-4PH precipitation hardened stainless steel
- UNS S30400 is SAE 304, Cr/Ni 18/10, Euronorm 1.4301 stainless steel
- UNS S31600 is SAE 316
- UNS S31603 is 316L, a low carbon version of 316
UNS series | Metal type(s) |
---|---|
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 |
See also
References
External links
- UNS Number Lookup, MatWeb Entering the UNS number shows a data sheet on the alloy.