Uns Unified Numbering System
Reference data and engineering information about uns unified numbering system for miscellaneous applications.
Overview
Engineering reference data for Uns Unified Numbering System in miscellaneous.
Key Formulas
Unit Conversion
Multiply by conversion factor.
Linear Interpolation
Estimate between two known points.
Percentage
Part as fraction of whole.
Variables
| Symbol | Description | Unit |
|---|---|---|
| Input value | — | |
| Output value | — | |
| Conversion factor | — |
UNS Series Identification
UNS Series | Metal / Alloy Category |
|---|---|
| A00001 to A99999 | Aluminum & aluminum alloys |
| C00001 to C99999 | Copper & copper alloys |
| D00001 to D99999 | Specified mechanical property steels |
| E00001 to E99999 | Rare earth & rare earthlike metals & alloys |
| F00001 to F99999 | Cast irons |
| G00001 to G99999 | AISI & SAE carbon & alloy steels (except tool steels) |
| H00001 to H99999 | AISI & SAE H-steels |
| J00001 to J99999 | Cast steels (except tool steels) |
| K00001 to K99999 | Miscellaneous steels & ferrous alloys |
| L00001 to L99999 | Low-melting metals & alloys |
| M00001 to M99999 | Miscellaneous nonferrous metals & alloys |
| N00001 to N99999 | Nickel & nickel alloys |
| P00001 to P99999 | Precious metals & alloys |
| R00001 to R99999 | Reactive & refractory metals & alloys |
| S00001 to S99999 | Heat & corrosion resistant (stainless) steels |
| T00001 to T99999 | Tool steels, wrought & cast |
| W00001 to W99999 | Welding filler metals |
| Z00001 to Z99999 | Zinc & zinc alloys |
Source: engineeringtoolbox.com
Understanding UNS: Not a Specification
A critical distinction of the UNS is that it is an identification system, not a specification. The UNS number itself does not dictate chemical composition, mechanical properties, or manufacturing processes. Instead, it provides a standardized way to reference a specific material that is defined by a separate specification (such as an ASTM, AMS, or SAE standard). This allows for clear communication and consistency across different industries and documentation.
Key Distinction
The UNS correlates and unifies existing numbering systems from organizations like ASTM and SAE into a single, consistent framework. For example, a material previously identified by an SAE number and an ASTM designation may be assigned a single, unique UNS number.