# Metal strength **URL:** \ **Category:** Factual Questions\ **Created:** [June 19, 2003, 12:54pm UTC](https://boards.straightdope.com/t/metal-strength/182906 "2003-06-19T12:54:19Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![draugrbane](https://avatars.discourse-cdn.com/v4/letter/d/bcef8e/32.png) [@draugrbane](https://boards.straightdope.com/u/draugrbane)\ **Post date:** [June 19, 2003, 12:54pm UTC](https://boards.straightdope.com/t/metal-strength/182906/1 "2003-06-19T12:54:19Z")
When describing the strength of metals, I notice people tend to talk all puffed up about a number they put before the metal. Like saying it is 6160 Aluminum or 6061 and the like. Other metals I have heard described were in the 3000 range or so. What do these numbers really mean? When I ask people after they say such a number, they usually look blankly for a while and then just say, “it means it is strong.” or some equal nonsense. ---
**Author:** ![chukhung](https://avatars.discourse-cdn.com/v4/letter/c/e79b87/32.png) [@chukhung](https://boards.straightdope.com/u/chukhung)\ **Post date:** [June 19, 2003, 1:34pm UTC](https://boards.straightdope.com/t/metal-strength/182906/2 "2003-06-19T13:34:08Z")
I believe in the case of aluminum, the numbers you refer to are the alloy designation. You may be interested in the information about these designators given here, [http://www.secat.net/tech%20alum%20designations%20121202.php](http://www.secat.net/tech%20alum%20designations%20121202.php) > [@](#): > > The modern aluminum alloy designation system, at least for wrought aluminum and wrought aluminum alloys, had its beginnings in 1954 when the Aluminum Association developed a 4-digit alloy designation system to address the need for a uniform system adequate for use by all. This system was later approved by the American National Standards Institute in the form of American National Standard H35.1, which was later expanded to also include the Association’s Temper Designation System. > … > For the wrought alloys, a 4-digit designation system is used in which the first digit is assigned based on the major alloying element(s). The last two digits in the 1xxx series used for alloys in which aluminum is 99.00% or greater reflect the minimum aluminum percentage above 99.00%, while in the 2xxx-8xxx families the last two digits have no special significance but serve only to identify the different aluminum alloys within the group. The second digit, if other than “0”, denotes modifications in composition to the original alloy. ---
**Author:** ![zut](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/zut/32/2875_2.png) [@zut](https://boards.straightdope.com/u/zut)\ **Post date:** [June 19, 2003, 4:17pm UTC](https://boards.straightdope.com/t/metal-strength/182906/3 "2003-06-19T16:17:29Z")
**chukhung** has it right: the numbers describing metals (6061 aluminum, for instance) have nothing to do with strength, per se, but simply designate the alloy used. However, certain alloys are in general stronger than others, and aluminum often has a temper designation (6061-T6, for instance), where the tempering process may give an increase in strength ([quick overview](http://shopswarf.orcon.net.nz/alalloy.html) of aluminum alloy/temper designations). You can’t really tell what the strength is from the alloy designation, though, except by knowing ahead of time which alloys and/or tempers are strongest. Alloy numbers themselves do not correspond to strength (so 6000 series aluminums are not three times stronger than 2000 series aluminums). Alloy designations exist for other metals, such as [steel](http://www.azom.com/details.asp?ArticleID=1378) and [copper](http://www.metserve.co.za/material/m_cu.htm) alloys, among others. [Here’s](http://www.metserve.co.za/material/m_.htm) a nifty overview of metals: more than you wanted to know. If the people you’re talking to are describing the strength of the material with the alloy designation, then you’ve correctly surmised that they don’t know what they’re talking about.