Talk:Aluminium alloy

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ASTM[edit]

User:Georgewilliamherbert's edit summary states that ASTM doesn't cover "structural alloys" except for tubing, and that the ASTM simply resells SAE standards. Neither statements are true. Off the top of my head, I routinely specify ASTM B221 for aluminium bar for structural applications. And although standards organizations have overlapping memberships and read each other's work, they still review and publish independently.--Yannick 03:31, 9 October 2006 (UTC)

The B211 standard states that it uses the standard ANSI H35.1 alloy numbering system, for which SAE produces the actual alloy composition and processing standards. I don't have the full B211 standard, however. Ref / cite within that doc which has actual alloy specs natively, and not a reference to another standard? Georgewilliamherbert 04:20, 9 October 2006 (UTC)
B221, not B211. But in any case, I'm guessing the SAE standard doesn't include the material testing specs, which are key to the ASTM work. If the standards cross-link to the same composition tables, that's good; it's harmonization of standards. But it doesn't give SAE a monopoly or primacy. Why would ASTM waste their time photocopying a bunch of me-too standards?--Yannick 04:34, 9 October 2006 (UTC)
Same composition and processing / heat treatment standards, strength standards, etc. The testing specs aren't part of the alloy's specification per se, though they are part of many uses (alloy 7075 with testing per ...). The SAE standard is the alloy - the rest is specific use and qualification requirements, not the alloy itself. One can do 7075 to the SAE spec without any additional testing. Georgewilliamherbert 05:06, 9 October 2006 (UTC)
But in many critical applications, the mechanical testing is considered an essential part of the alloy's specification. In those cases, 7075 with an ASTM spec is used, and untested materials are rejected. This is largely the raison d'etre of the ASTM specs. Some engineers for some applications use the SAE standards. Other engineers for different applications use the ASTM standards. And then there are AMS specs, EN specs, DIN, etc. Wiping out any reference to standards other than SAE is not justifiable.--Yannick 23:26, 9 October 2006 (UTC)
OK, I checked ASTM B211, B221 and a few others today, and they do include detailed composition tables and processing standards. They do refer to ANSI H35.1 for nomenclature, but H35.1 does not reference any SAE standards. Instead, it has a footnote stating that specific alloys are registered with the Aluminum Association. (Which, by the way, seems to sell some of those industry statistics that might solve the linkspam issue below.) I don't have as much experience with the SAE standards, but there is no doubt in my mind that (a) the ASTM aluminum alloy standards are used independently of the SAE standards, and (b) they cover many shapes other than tubing. There is nothing more "native" about the SAE standards than the ASTM standards.--Yannick 22:39, 10 October 2006 (UTC)

Linkspam[edit]

Ytrottier, why do you think the reference to Alcoa's aerospace alloys page is linkspam? It's a good list of commonly used aerospace alloys... Georgewilliamherbert 04:23, 9 October 2006 (UTC)

The fact that these alloys are marketed says nothing about their prevalence in the field. If you want to make statements about which alloys are most commonly used, they should be based on market surveys, not marketing materials. Linking to a vendor is generally frowned upon in Wikipedia, except in very specific circumstances. I don't think this qualifies.--Yannick 04:30, 9 October 2006 (UTC)

Linking to a vendor is fine, as long as it's not to an advertising related page. Often vendors are the best descriptive references for something. I'm not a WP newbie. It's hard to do a marketing survey, as most of the details are proprietary and hard to get unless you own the aircraft... Much of it is public, but not sufficiently enough to do a good survey. Georgewilliamherbert 04:57, 9 October 2006 (UTC)
Market survey, not marketing survey. You don't need to own any aircraft for that. Many industry analysts compile data from various manufacturers about their outputs, and publish the statistics. Try a good university library, if you feel it's important to talk about the relative sale volumes of various alloys. If you can't get your hands on a document you can cite, I do not encourage you to do your own market survey; that would be original research. The page you linked to was, at best, an infomercial page, and it did not substantiate your claim that these alloys are most common. At best, we can only say that these alloys are representative.--Yannick 23:33, 9 October 2006 (UTC)

8000 series[edit]

I was under the impression that the 8000 series was solely for the Al-Li based alloys, and not just 'others' as this article suggests. Is this right? Mike 20:37, 25 April 2007 (UTC)

8000 series is an open category, used for compositions not covered by any of the other 7. Sigmund 15:08, 9 May 2007 (UTC)


Move individual alloy pages to alloy series[edit]

I suggest we create separate articles for each alloying system and move all the different alloy articles, 6061, 7075 etc, into their respective alloy series page, e.g. 6xxx series, 7xxx series etc. Otherwise there would be a whole lot of duplicated text for alloys that share the same properties. Sigmund 15:17, 9 May 2007 (UTC)

Worth talking about at least. What about the other alloy designation systems (non-wrought alloys, etc)? Georgewilliamherbert 17:22, 9 May 2007 (UTC)
It's possible to do the same for cast alloys, although the nomenclature is not that standardized. Maybe it's better to create articles with descriptive (ISO) nomenclature such as Al-Cu alloys, Al-Mg alloys, Al-Mg-Si alloys, etc. Then there could be two main sections, one for cast and one for wrought alloys. Sigmund 10:57, 14 May 2007 (UTC)

Yes, 8000 series is reserved for Lithium Alloys —Preceding unsigned comment added by 83.105.85.133 (talk) 16:36, 26 January 2009 (UTC)

New section[edit]

This is all interesting info but I don't think it's very relevant to the article. If others do, then they can reinstate it.

===Most common alloys, by search engine hits===
These alloys had the most search engine hits (Google Hits + Altavista Hits / 2). Listed is order for most to least hits. 50 different alloys were checked, the top 15 are shown. 
the search string for google was "[alloy number] (aluminum OR aluminium) alloy", and the search string for altavista was "[alloy number] NEAR (aluminum OR aluminium) NEAR alloy".

* 6061 aluminium
* 7075 aluminium
* 1100 aluminium
* 6063 aluminium
* 2024 aluminium
* 1050 aluminium
* 2017 aluminium
* 5052 aluminium
* 3003 aluminium
* 1060 aluminium
* 7005 aluminium
* 2014 aluminium
* 6005 aluminium
* 5182 aluminium
* 3004 aluminium

--Wizard191 (talk) 12:09, 13 April 2008 (UTC)

I originally put that in so I could use it as a reference for the aluminium recycling page, i.g. "The top 5 aluminium alloys produced are apparently 6061, 7075, 1100, 6063, and 2024.". Do you know of any other references I can use instead? --98.214.11.170 (talk) 23:48, 13 April 2008 (UTC)
No offense, but I think your logic is a little flawed. Simply because a search engine or two gives the most results for x, y, z aluminium alloy doesn't mean that it's the most produced alloy. I recommend that you search for production values for aluminium alloys. --Wizard191 (talk) 12:53, 14 April 2008 (UTC)
Statistically speaking (the only flaw was a sample size of two search engines) the deviations between alloy hits was enough to justify the non assertive reference I made about the top 5 alloys in the aluminium recycling page. I do see your point, and agree with you though. Where can I find an authoritative reference for the top 5 aluminium alloys produced? Apparently I'm not searching in the right places because I can't find any.--98.214.11.170 (talk) 15:16, 14 April 2008 (UTC)
I don't know where you can find that information, but I just realized that this can't be reinserted because this qualifies as original research (see WP:NOR) --Wizard191 (talk) 17:05, 14 April 2008 (UTC)
Yes it does qualify as original research. The problem is, if your a backyard metal caster and hobby machinist like me you don't have access to a spectroscopy machine to determine the alloy type. This makes knowing the production statistics and the properties and applications of the top alloys the next best thing for identifying scrap aluminium to melt.--98.214.11.170 (talk) 02:47, 15 April 2008 (UTC)

heat number[edit]

does anyone know what the numbers mean after the letters? I.E. 7178 HXXX what do the x's mean? —Preceding unsigned comment added by 24.231.190.221 (talk) 16:46, 18 August 2008 (UTC)

The XXX are place holders. The first X can be a 1,2,3, or 4 and designate how the material was processed to the desired property limit . The second X designates the strength level, with 8 designating full hard, 4 being half hard, and 2 being quarter hard. The third X designates a special practice/condition within a Hxx practice. The H is for work hardening alloys/products. In other words, the property level desired is obtained by working the metal. There are other tempers, including T (solution heat treated, with an array of XXX in its own right), O (full annealed), W (solution heat treated in process), and F (in process). This designation system is also used Magnesium Alloys. —Preceding unsigned comment added by 69.48.113.50 (talk) 21:06, 21 April 2009 (UTC)

aircraft aluminium[edit]

I came to this entry to find out more about aircraft aluminium. Plenty of flashlight companies and others claim their product is made from aircraft aluminium, so i came to see what the general consensus as to what it is. --71.121.14.132 (talk) 04:11, 6 December 2008 (UTC)

I've added a note about this to the article. Wizard191 (talk) 23:58, 21 April 2009 (UTC)
Two things make me curious here... First, in the opening paragraph it says "Aluminium alloys can be improperly heat treated. This causes internal element separation, and the metal then corrodes from the inside out. Aircraft mechanics deal daily with aluminium alloy corrosion." I won't add 'citation needed' because that's rude, I have no doubt this is true, I'm just curious about it, some direct linkage might help, and it may be interesting enough for someone knowlegeable to add a bit of detail about this to the article. The second point of interest for me is about flashlight metal, as mentioned by the first poster in this section, and it relates to my first curiosity too... In Nitecore's 2015 catalog there is a new flashlight design described as die cast, but twice as strong as their standard machined metal. I always thought that cast almuninium was weaker than wrought aluminium (presumably that includes cold rolled machinable stock), so this is interesting. Firstly, if it's true, how so? Secondly, does the method run the risk of the type of internal corrosion that may result from the heating required to cast it? If this really works it's an excellent system for avoiding waste energy and material, and for gaining strength, and Nitecore seem to claim this as a new method, while I suspect that if this were possible, it might have been known widely for a long time by now. 86.157.53.38 (talk) 12:43, 11 June 2016 (UTC)
No idea on the flashlight. Increased strength may be true of some properties, but not necessarily characteristics that are important for a flashlight. i.e. marketing hype. If you have the time, perhaps you could email the company and ask for a link to a paper on this.
The statement about internal corrosion does need a citation and I added a {{citation needed}} tag. That information is of interest to me as well and I added a comment requesting expansion. BTW: It is usually best to add something like this to the bottom of the page as most are going to look under a 7 y.o. comment. Cheers Jim1138 (talk) 18:25, 11 June 2016 (UTC)

Corrosion Protection[edit]

Can somebody add info about protecting from corrosion (powder coating etc), it would be appreciated. Chendy (talk) 15:13, 31 March 2009 (UTC)

Special Request: Identification methods.[edit]

I have a special request for the experts out there. I'd like to be able to identify alloys so I can check scrap pieces of Aluminum in my garage for suitability for casting, anodizing, welding processes, etc. Can anybody out there share any tips such as an acid test for the presence of copper? Rick brade (talk) 14:21, 30 May 2009 (UTC)

This is not a forum. Please take your inquiry to the WP:HELP DESK. Wizard191 (talk) 14:31, 30 May 2009 (UTC)

Scandium in aluminum alloys[edit]

The Scandium article mentions that there are positive benefits of alloying Scandium with Aluminum; e.g. strength. There seems to be no mention of Scandium in this article on Aluminum alloys. Any ideas why? Is the info in the Scandium article incorrect? N2e (talk) 19:58, 31 July 2009 (UTC)

Here is a comment from the Scandium talk page:
Usage in Al Alloys - The Al3Sc Compound and Point of Grain Refinement

"There is serious research - e.g. by David Dunand's group at Northwestern and significant prior art (and patents?) - on using The L12 Al3Sc compound as a strengthening precipitate, since it is coherent and hence has low surface energy. Therefore Al3Sc ppts will only coarsen slowly and Al alloys strengthened by such means should have relatively good high temperature stability and creep resistance. The goal is 250+ C as a service temperature, e.g. at a service stress of 100 MPa less than 1% creep strain in 5000+ hrs. Someone interested with access to scientific journals and a patent search should probably add this into the alloys section. Also, there are lots of purposes to adding Sc asa grain refiner (eg in welds) other than Hall-Petch strengthening. For example; hot shortness in castings due to microsegregation and dendrite arm spacing (weld solidification cracking), which was the purpose identified in the original Russian patents translated by TWI in Abington, Cambs, UK. Another reason might be improved fatigue resistance and reduced microsegregation in itself. Recommendation: An expert in Al-Sc metallurgy should edit this section so that it actually reads correctly to a metallurgist; at the moment its a bit confused."David.dye (talk) 19:30, 31 December 2008 (UTC)

And here is a relevant section of the main Scandium article, with several citations included:

"The addition of scandium to aluminium limits the excessive grain growth that occurs in the heat-affected zone of welded aluminium components. This has two beneficial effects: the precipitated Al3Sc forms smaller crystals than are formed in other aluminium alloys[1] and the volume of precipitate-free zones that normally exist at the grain boundaries of age-hardening aluminium alloys is reduced.[2] Both of these effects increase the usefulness of the alloy. However, titanium alloys, which are similar in lightness and strength, are cheaper and much more widely used.[3]"

It seems to me that this reasonably well-cited and verifiably sourced text could probably fit into the Aluminum alloy article quite well. Anyone who knows more about the subject matter of metal alloys want to have a go at it? N2e (talk) 20:49, 31 July 2009 (UTC)
In the absence of any subject-matter experts on Aluminum alloys coming forward, I have made an initial attempt to improve the Aluminum Alloy article with the addition of a section of very well-cited text on Al-Sc alloys from the Scandium article. N2e (talk) 03:30, 28 September 2009 (UTC)

References

  1. ^ Fuller, Christian B. (June 2003). Temporal Evolution of the Microstructures of Al(Sc,Zr) Alloys and Their Influences on Mechanical Properties (PDF) (PhD thesis). Northwestern University. Retrieved 2008-10-21.
  2. ^ Ahmad, Zaki (February 2003). "The properties and application of scandium-reinforced aluminum" (PDF). JOM. 55 (2): 35. doi:10.1007/s11837-003-0224-6.
  3. ^ ed. by James A. Schwarz .... (2004). James A. Schwarz, Cristian I. Contescu, Karol Putyera. CRC Press. p. 2274. ISBN 0824750497.

'Refideas' change[edit]

Link for 'refideas' was broken I corrected it and add new one with addendum.

I also added two alloys but before adding next ones I might ask: "can I?". And to answer any "why" questions - this is because those two alloys (5754 and 7022) are quite popular in Europe.

I'd like also to add several alloys like: 2017, 'HOKOTOL', 'GIANTAL', because they are unique and interesting (especially HOKOTOL which has 180 HB - this is 30 HB more than 7075) McDardy (talk) 13:17, 5 January 2011 (UTC)

Yeah, feel free to expand the table! The only thing that would be helpful is to supply a reference for each line you add. You can do this by adding <ref>Reference information</ref> after the name of the alloy. Wizard191 (talk) 18:49, 5 January 2011 (UTC)

Suggest merge[edit]

6061 aluminium alloy substantially duplicates the content of this article and could usefully be merged here for context and to reduce redundancy. Discussing the alloys at one place would give the reader a better understanding of their relative properties and uses. --Wtshymanski (talk) 19:10, 4 April 2012 (UTC)

  • oppose Aluminium alloys are a huge topic. 6061 are significant enough just on their own to justify a stand-alone article. Andy Dingley (talk) 21:43, 4 April 2012 (UTC)
  • oppose - Some alloy characteristics can be here, but from a sane data management point of view I can't imagine putting every alloys' characteristics for every temper / work hardening level all in one big article. No. Separate page per alloy with a little summary info here... And yes, 6061 is extremely significant across many industries. Georgewilliamherbert (talk) 23:34, 4 April 2012 (UTC)

Aluminium-Magnesium alloys[edit]

This section is confusing: "Aluminium-magnesium alloys are both lighter than other aluminium alloys and much less flammable than alloys that contain a very high percentage of magnesium". I think it should be made clear that the Aluminium-Magnesium alloys referred to contain only about 1% Magnesium. Biscuittin (talk) 10:41, 14 June 2012 (UTC)

e.g. 2024 aluminium alloy, 6061 aluminium alloy, 6063 aluminium alloy. Biscuittin (talk) 10:44, 14 June 2012 (UTC)
And what are the "other aluminium alloys" that they are being compared with? Biscuittin (talk) 10:49, 14 June 2012 (UTC)
If it is Aluminium bronze, containing only about 10% Aluminium, then I would agree, but I think we need more information. Biscuittin (talk) 10:52, 14 June 2012 (UTC)
"Aluminium magnesium alloys" or the Magnalium range generally refers to two distinct groups:
Elektron and the like, which are casting alloys. These may have significant magnesium contents, up to the majority >50%, where the aluminium is present to improve the corrosion resistance of a pure magnesium casting alloy (Mg rich alloys are generally unworkable in service for this reason, unless they're an esoteric application that can afford very careful looking after)
Secondly the sheetmetal alloys like Birmabright, which are 5-15% Mg, added to harden the sheet. Pure aluminium alloys are too soft to survive in service and collect small dents. These were developed for aircraft, but are also used for car bodywork.
Most aluminium alloys though are still derived from Duralumin, with a few % of Cu. There's no need to drag the relatively obscure aluminium bronzes (hardwearing, but a pig to machine) into this question. Andy Dingley (talk) 11:02, 14 June 2012 (UTC)
I am questioning the statement "Aluminium-magnesium alloys are... lighter than other aluminium alloys". What are the "heavy" aluminium alloys they are being compared with? I have suggested aluminium bronze. Can you suggest others? Biscuittin (talk) 13:03, 14 June 2012 (UTC)
Al-Mg casting alloys are lighter than pure Al and also lighter than the commonplace Al-Cu alloys. We don't need to bring the (quite heavy, and certainly obscure) Al bronzes into this. The Al-Mg sheet alloys would be lighter too, if you cared to weigh them, but not significantly so in practical terms. Andy Dingley (talk) 13:39, 14 June 2012 (UTC)
You are not answering my question. What "heavy" aluminium alloys are there, apart from aluminium bronze? It seems to me that most aluminium alloys are about 95% aluminium, so the content of the remaining 5% is not going to make much difference to the density. Biscuittin (talk) 16:12, 14 June 2012 (UTC)
You're the only one looking for "heavy" aluminium. The original text here isn't.
Casting alloys have much more Mg than 5% - even up to about 50%. Even the harder sheet alloys are mostly about 10%, so more than 5%. Andy Dingley (talk) 16:45, 14 June 2012 (UTC)
I return to the sentence in the article: "Aluminium-magnesium alloys are both lighter than other aluminium alloys and much less flammable than alloys that contain a very high percentage of magnesium". What are they lighter than? If this question cannot be answered then the sentence should be deleted as meaningless and unsourced. Biscuittin (talk) 16:54, 14 June 2012 (UTC)
Pretty obviously it refers to the casting alloys, as they're the ones where weight matters most, where the volume is enough that density can make any difference (thin light sheet is always going to be "light", unless you're making aircraft). These are also the alloys where their appreciable Mg content can be enough to reduce their density to about 2/3rd of that for pure Al. The common alloys otherwise would be 6061 (Mg-Si, but not much of either) which is the same density as plain Al or the 2000 series durals (Cu) which are about 5% heavier than plain Al. Andy Dingley (talk) 20:50, 14 June 2012 (UTC)
Can you be specific about what alloy is being compared with what other alloy? If not, the sentence is meaningless and should be removed. You are normally very insistent that all statements should be referenced. Why is this one an exception? Biscuittin (talk) 21:51, 14 June 2012 (UTC)
Are you aware that magnesium is less dense than aluminium? Otherwise I cannot imagine what is confusing you. I've already cited a whole bunch of alloys. The lightest of the lot is the Elektron series, the aluminium-magnesium alloys that are described as being lighter. Andy Dingley (talk) 22:47, 14 June 2012 (UTC)
Yes, I am aware that magnesium is less dense than aluminium. What I am complaining about is the wooliness of the statement. Effectively it says: "Alloys of magnesium with aluminium in unspecified proportions are both lighter than other aluminium alloys and much less flammable than unspecified alloys of unspecified composition that contain a very high percentage of magnesium". This is so vague as to be meaningless. Biscuittin (talk) 07:32, 15 June 2012 (UTC)
The only useful thing the statement is saying is "Low-magnesium alloys are generally less flammable than high-magnesium alloys". This is more relevant to the magnesium alloy article than this one. Biscuittin (talk) 08:36, 15 June 2012 (UTC)
Even if the alloys are unspecified, the numbers are such that the statement (perhaps surprisingly) remains true in the general case, as well as in some specific case. You could of course reword it to be more specific, but the drawback there is the usual WP one of over-convoluted text trying too hard to remain absolutely true in all cases, at the cost of readability.
"Aluminium-magnesium alloys" refers to Elektron and Birmabright, with a substantial Mg content. No competent reader should interpret this as also implying the 6061 series with a trace 1% or so of Mg, even though that's the alloy series based on Mg-Si. Named alloys are not (and never have been) named merely on their set of elements as listed in a textbook, but also on their proportions, their structure and their resultant properties. The names are assigned from the history of people working with the alloys (where their properties become obvious) not just from a textbook listing. Dural isn't an aluminium bronze, even though it contains Cu. Cast iron contains iron and carbon, but we don't call it steel. Andy Dingley (talk) 09:15, 15 June 2012 (UTC)

I return again to the sentence in the article: "Aluminium-magnesium alloys are both lighter than other aluminium alloys and much less flammable than alloys that contain a very high percentage of magnesium". You refer to "Elektron and Birmabright, with a substantial Mg content". Are you claiming that Aluminium alloys with a high magnesium content are less flammable than non-Aluminium alloys with a high magnesium content? If so, which non-aluminium alloys are you comparing them with? Your reference to "No competent reader" seems to imply that Wikipedia is for experts alone and not general readers. I point out again that the statement is completely unreferenced. Biscuittin (talk) 10:00, 15 June 2012 (UTC)

It's misleading to refer to this one sentence in isolation. It has always been a two sentence paragraph.
Alloys composed mostly of the two lightweight metals aluminium and magnesium have been very important in aerospace manufacturing since somewhat before 1940. Aluminium-magnesium alloys are both lighter than other aluminium alloys and much less flammable than alloys that contain a very high percentage of magnesium.
This gives an additional context: the alloys being described are two component aluminium - magnesium alloys. It's pretty obvious that these include Elektron and Birmabright, but not 6061.
"non-Aluminium alloys with a high magnesium content" Which are? I'm unaware of any high magnesium alloys except for aluminium magnesium and pure magnesium. I'm sure someone has studied magnesium-lithium too, but I'm not aware that it's used for structural purposes (I think its only application so far has been for batteries). The point about flammability is that it's much harder to ignite an Al-Mg or Mg-Al Elektron alloy than pure Mg. No comparison is intended with any other alloys.
Of course en:WP isn't written for experts, but it is written on the assumption of some reasonable intelligence, English language skills and some level of background. simple:WP is there to address the language issue. It's impossible to write an article on a complex topic without assuming some background (which should of course be linked or covered in the lead). Attempting to make every paragraph self-supporting from first principles is not a good approach, as it leads to unreadable articles for everyone. Have you ever tried to read a section of Principia Mathematica? It's the most utterly correct textbook ever constructed (with a slight nod to Don Knuth), but it's also useless as any sort of tutorial. Andy Dingley (talk) 11:24, 15 June 2012 (UTC)
I have added a "citation" tag and I am not going to waste any more time on it. Biscuittin (talk) 15:45, 15 June 2012 (UTC)

Silver?[edit]

Nothing about aluminum-silver alloys? http://www.visualcapitalist.com/silver-undercover-super-metal/

Aluminium alloys versus types of steel

"In general, stiffer and lighter designs can be achieved with aluminium alloys than is feasible with steels. For instance, consider the bending of a thin-walled tube: the second moment of area is inversely related to the stress in the tube wall, i.e. stresses are lower for larger values. The second moment of area is proportional to the cube of the radius times the wall thickness, thus increasing the radius (and weight) by 26% will lead to a halving of the wall stress."

Not true at all. the second moment of area is inversely related to the stress in the tube wall only when the distance (z in the link given) from the neutral axis to a point of interest is kept constant! Therefore the conlusion thus increasing the radius (and weight) by 26% will lead to a halving of the wall stress is a false one. See: http://en.wikipedia.org/wiki/Euler%E2%80%93Bernoulli_beam_theory#Simple_or_symmetrical_bending sigma = M * z / I = M * r / I In the formula in the link above, z in this case is same as radius r. Therefore 26% increase of r will lead to new I = 2* old I, but the new stress = old stress / (1.26)^2 for the same M.

In other words, it's a square relationship, not cubed one. 86.50.116.35 (talk) 15:10, 9 November 2014 (UTC)

What is composition of Al 7037[edit]

1100mph wheel spin test refers to Al 7037 as aerospace-grade aluminium (used in wheels of Bloodhound SSC) but it's not mentioned here. - Rod57 (talk) 13:26, 2 March 2015 (UTC)

@Rod57: apparently it's:
  • Al: 86.54–90.24 % (balance)
  • Zn 7.8–9.0 %
  • Mg 1.3–2.1 %
  • Cu 0.60–1.1 %
  • Zr 0.06–0.25 %
  • Mn ≤ 0.50 %
  • Si ≤ 0.12 %
  • Fe ≤ 0.10 %
  • Ti ≤ 0.10 %
  • Cr: ≤ 0.04 %
  • Other, each ≤ 0.05 %
  • Other, total ≤ 0.15 %
23.83.37.241 (talk) 21:13, 16 January 2018 (UTC)

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How are various alloys defined?[edit]

One thing that's not clear is what the definition of e.g. 1350 alloy is. Specifically, does any uniform aluminium alloy with the specified composition qualify? Or are there additional qualifications?

By composition, 1199 alloy (99.99% pure) meets the specs for almost all of the 1xxx series, which specify only upper bounds on alloying elements. May I therefore substitute 1199 anywhere that 1350 is called for?

This seeme wrong because comparing http://www.hmwire.com/New%20PDFs/Aluminum_1199_Information.pdf to http://www.hmwire.com/New%20PDFs/Aluminum_1350_Information.pdf, things like tensile strength differ by a significant factor. E.g. 10 MPa yield strength for 1199-0 vs. 27.6 MPa for 1350-0.

In all of the lists of properties I see on-line in various manufacturers' data sheets, it's not clear which properties other than composition are the guaranteed defining properties, and which are merely "typical values" for informational purposes.

Does anyone know? 23.83.37.241 (talk) 11:12, 19 January 2018 (UTC)

Notation AA nnnn[edit]

In DPA p24 it refers to various aluminium alloys used in aerospace as AA nnnn - with the nnnn seeming to match some in this WP article. Does the "AA" just stand for "aluminium alloy" and is this usage common (or restricted to some industries) or officially sanctioned ? (DPA article refers to AA 2024/2014/5052/6061/7050/7068/7075/2219 (used in first Space Shuttle ET flown)/6063/7475. - Rod57 (talk) 19:16, 12 July 2018 (UTC)