Instructions: The UNS number (short for "Unified Numbering System for Metals and Alloys") is a systematic scheme in which each metal is designated by a letter followed by five numbers. It is a composition-based system of commercial materials and does not guarantee any performance specifications or exact composition with impurity limits. Other nomenclature systems have been incorporated into the UNS numbering system to minimize confusion. For example, Aluminum 6061 (AA6061) becomes UNS A96061.

Overview of the UNS system

This is an overview of the UNS system, with special emphasis on common commercial alloys. As with any system, there are ambiguities such as the distinction between a nickel-based superalloy and a high-nickel stainless steel.

• Axxxxx - Aluminum Alloys
• Cxxxxx - Copper Alloys, including Brass and Bronze
• Fxxxxx - Iron, including Ductile Irons and Cast Irons
• Gxxxxx - Carbon and Alloy Steels
• Hxxxxx - Steels - AISI H Steels
• Jxxxxx - Steels - Cast
• Kxxxxx - Steels, including Maraging, Stainless Steel, HSLA, Iron-Base Superalloys
• L5xxxx - Lead Alloys, including Babbit Alloys and Solder Alloys
• M1xxxx - Magnesium Alloys
• Nxxxxx - Nickel Alloys
• Rxxxxx - Refractory Alloys
• R03xxx- Molybdenum Alloys
• R04xxx- Niobium (Columbium) Alloys
• R05xxx- Tantalum Alloys
• R3xxxx- Cobalt Alloys
• R5xxxx- Titanium Alloys
• R6xxxx- Zirconium Alloys
• Sxxxxx - Stainless Steels, including Precipitation Hardening Stainless Steel and Iron-Based Superalloys
• Txxxxx - Tool Steels
• Zxxxxx - Zinc Alloys

About 75% of the metal data sheets in MatWeb have a UNS number that has been tied to its particular entry. You may easily find such metals by typing the UNS number in the Quick Search box in the upper right of this page. You may also make your selection from inside the boxes below and click on the appropriate 'Find' button. You can then follow the links to the complete technical data on MatWeb's extensive list of aluminum, copper, lead, magnesium, tin, titanium, nickel, stainless steel, and other metal alloys.

This page lists every UNS Number that is included in the MatWeb database. For cases in which our sources do not state a UNS Number, whether or not such a number has been assigned, then it will not appear on this page. You can also use our Index of Engineering Materials page to search by metal type such as titanium alloy or tool steel or use our Metal and Alloy Composition Search for a systematic search based on an alloy's component elements. Regardless of how you navigate through MatWeb, you will find detailed technical property data such as tensile strength, elastic modulus, thermal conductivity, and coefficient of thermal expansion.

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