ASTM-E527 › Standard Practice for Numbering Metals and Alloys in the Unified Numbering System (UNS)
The following bibliographic material is provided to assist you with your purchasing decision:
Scope
1.1 This practice (Note 1) covers a unified numbering system (UNS) for metals and alloys that have a "commercial standing" (see Note 2), and covers the procedure by which such numbers are assigned. Section 2 describes the system of alphanumeric designations or "numbers" established for each family of metals and alloys. Section 3 outlines the organization established for administering the system. Section 4 describes the procedure for requesting number assignment to metals and alloys for which UNS numbers have not previously been assigned.
Note 1-UNS designations shall not be used for metals and alloys that are not registered under the system described herein, or for any metal or alloy whose composition differs from those registered.
Note 2-The terms "commercial standing," "production usage," and others are intended to portray a material in active industrial use, although the actual amount of such use will depend, among other things, upon the type of materials. (Obviously gold will not be used in the same "tonnages" as hot-rolled steel.) Different standardizing groups use different criteria to define the status that a material has to attain before a standard number will be assigned to it. For instance, the American Iron and Steel Institute requires for stainless steels "two or more producers with combined production of 200 tons per year for at least two years"; the Copper Development Association requires that the material be "in commercial use (without tonnage limits)"; the Aluminum Association requires that the alloy be "offered for sale (not necessarily in commercial use)"; the SAE Aerospace Materials Division calls for "repetitive procurement by at least two users." While it is apparent that no hard and fast usage definition can be set up for an all-encompassing system, the UNS numbers are intended to identify metals and alloys that are in more or less regular production and use. A UNS number will not ordinarily be issued for a material that has just been conceived or that is still in only experimental trial.
1.2 The UNS provides a means of correlating many nationally used numbering systems currently administered by societies, trade associations, and individual users and producers of metals and alloys, thereby avoiding confusion caused by use of more than one identification number for the same material; and by the opposite situation of having the same number assigned to two or more entirely different materials. It also provides the uniformity necessary for efficient indexing, record keeping, data storage and retrieval, and cross referencing.
1.3 A UNS number is not in itself a specification, since it establishes no requirements for form, condition, quality, etc. It is a unified identification of metals and alloys for which controlling limits have been established in specifications published elsewhere.
Note 3-Organizations that issue specifications should report to appropriate UNS number-assigning offices (3.1.2) any specification changes that affect descriptions shown in published UNS listings.
Keywords
Metals and alloys numbering system; Numbering system (UNS); UNS (Unified Numbering System); Unified Numbering System (UNS) for metals/alloys, practice
To find similar documents by ASTM Volume:
01.01 (Steel--Piping, Tubing, Fittings)
To find similar documents by classification:
77.120.01 (Non-ferrous metals in general)
This document comes with our free Notification Service, good for the life of the document.
This document is available in either Paper or PDF format.
Customers who bought this document also bought:
ASTM-A276Standard Specification for Stainless Steel Bars and Shapes
ASTM-A484
Standard Specification for General Requirements for Stainless Steel Bars, Billets, and Forgings
ASTM-A240
Standard Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and for General Applications
Document Number
ASTM-E0527-23
Revision Level
2023 EDITION
Status
Current
Modification Type
Reapproval
Publication Date
Sept. 26, 2023
Document Type
Practice
Page Count
7 pages
Committee Number
A01.91