Talk:Annealing (materials science)

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This article is written in American English, which has its own spelling conventions (color, defense, traveled) and some terms that are used in it may be different or absent from other varieties of English. According to the relevant style guide, this should not be changed without broad consensus.

I've heard of a process used in aerospace engineering where turbine fan blades are formed from a single chrystal. Is that what this process is and how would slow-cooling, which creates softness, be a desired property of a jet engine turbo fan blade?

I'm not sure what it's called, but the process definitely exists. I believe it was developed by GE in order to reduce creep from centripetal force. I saw a picture of a turboprop blade made of it in a biomaterials class. --Hyperspite 02:27, 6 February 2007 (UTC)[reply]

• Annealing is not used to create a turbine thats a single crystal. That requires a very complex manufacturing process.

Turbine blades are created in a different way using a series of processes, after my exams i will go through it on a new page (if i cant find one that already exists).Also, this article needs a fair few changes, I like the wording used for much of it but material properties need expanding and qualifing, The physical process needs expanding and pictures, example and citations need adding. I'm happy to do this in a few weeks provided no-one beats me to it. Sam Lacey 00:09, 18 May 2007 (UTC)

Is this a mistake?

If scale is to be avoided, annealing is carried out in an oxygen, carbon, and nitrogen free atmosphere (to avoid oxidation, carburization, and nitriding respectively) such as endothermic gas (a mixture of carbon monoxide, hydrogen gas, and nitrogen).

If we need an atmosphere free of oxygen, carbon, and nitrogen, why would we use a gas that contains forms of all three? Confusing.

Scott Johnson 15:21, 7 June 2007 (UTC)[reply]

I divided the page of Full annealing. I am sorry for that because I am not sure about copyright... I added some picture to clearify the full annealing.(georgelade:17 April 2008) —Preceding unsigned comment added by Georgelade (talk • contribs) 10:31, 17 April 2008 (UTC)[reply]

Why? The article isn't really big enough to dedicate a seperate article for

Full annealing Iepeulas (talk) 23:28, 30 May 2008 (UTC)[reply

]

This section describes full annealing only as it applies to steel. Austenite and cementite are phases specific to steel only. I suggest a more general description for any metal / metal alloy. — Preceding unsigned comment added by Galdar84 (talk • contribs) 19:12, 29 September 2011 (UTC)[reply]

I ran across this parenthetical, "(about 50 °F above C3 line)". What is a C3 line? Also, should there be a space between "50" and "°F"? Lon of Oakdale (talk) 19:39, 1 May 2008 (UTC)[reply]

I did the merge (just copy and paste) and placed a redirect in

Dhumphus (talk) 10:17, 13 March 2010 (UTC)Could someone please link the the word quench [hardening] under Setup & equipment section to the appropriate Wiki article. It has been mentioned previously, but is there any info on the phrase C3 Line?[reply]

C3 refers to a line in the iron-carbon phase diagram. I've removed it because the article should be about annealing in general. Wizard191 (talk) 14:55, 13 March 2010 (UTC)[reply]

The difference between tempering and annealing needs to be clearly explained. Does annealing increase hardness while tempering reduces it? -- Beland (talk) 02:47, 24 June 2010 (UTC)[reply]

In general, they'll both reduce hardness. However tempering is a treatment that's mostly relevant to carbon steels (or alloys that have transition behaviours as carbon steel does) and is primarily done for the sake of this hardness. Annealing is most commonly encountered for ductile metals like copper or silver, where it's a question of removing crystalline dislocations to reduce previous work-hardening and make them ductile again, so that they can be worked further. Even here, "work hardening" is more about fatigue than it is about hardness.

Also watch out for an archaic use of "tempering" to mean "hardening and tempering". It's obscure (medieval armourer's texts, and that dreadful but unaccountably popular Weyger book). Andy Dingley (talk) 09:38, 24 June 2010 (UTC)[reply]

What is the temperature range for annealing process? — Preceding unsigned comment added by 2409:4060:2116:A024:7D8B:7ACF:B00F:D8C0 (talk) 16:33, 7 November 2018 (UTC)[reply]

It is kindly requested that this article shall contain a separete section about nuclear reactor vessel annealing, which is done more and more often to PWRs to extend their useful lifespan to 35-40 years. 82.131.134.203 (talk) —Preceding undated comment added 23:17, 17 January 2011 (UTC).[reply]

1.^ http://www.handyharmancanada.com/hbpm/silver/silver.htm

This link is the first of the references but it does not work. Without a working link all the information referenced from this link is in need of a new citation.

Joshua Harden (talk) 16:27, 27 June 2012 (UTC)[reply]

tagged dead link Glrx (talk) 17:31, 29 June 2012 (UTC)[reply]

This link refers to another article that is unrelated and confuses the meaning in this article. The linked article states "a critical point, also known as a critical state, occurs under conditions (such as specific values of temperature, pressure or composition) at which no phase boundaries exist. There are multiple types of critical points, including vapor–liquid critical points and liquid–liquid critical points." and does not seem to relate to the usage the term here. Since I had changed the definite article "the" to an indefinite one "a" and somebody reverted my edit I have removed the link in this article to introduce less confusion to the reader. Please read the text and follow the link before reverting. 174.118.141.197 (talk) 03:10, 24 August 2013 (UTC)[reply]

Either a link to a proper Wikipedia page that covers this, or a citation of an external source should be included 101.174.62.1 (talk) 10:44, 18 September 2013 (UTC)[reply]

this article contains absolutely nothing on the history of these developments * supposedly jake Barnett*s - the autistic genius - grampa had a jot to do with this * 74.78.15.101 (talk) 17:13, 6 May 2014 (UTC)grumpy[reply]

Dear All,

I have faced one problem at the time of hot forging of component if the brass rods tensile or hardness in hard condition your component will be a not forged properly. So annealed the materiel in 250C -4 hours after you will defiantly get the proper component in forging process.

Rahul Rathod

I feel that the language used in the Thermodynamics section is very technical and is probably only understood by people that already know all about annealing. Particularly, this sentence- "The decarburization mechanism can be described as three distinct events: the reaction at the steel surface, the interstitial diffusion of carbon atoms and the dissolution of carbides within the steel.[3] " Makes little sense to me as part of this section. Suddenly it says The decarburization mechanism, as if we had already established that this unexplained thing is part of Annealing.

IceDragon64 (talk) 21:12, 9 November 2014 (UTC)[reply]

The opening paragraph says that ferrous metals are NOT suitable for quench hardening and copper is. The Setup and Equipment paragraph says the opposite. Which is right?

IceDragon64 (talk) 21:22, 9 November 2014 (UTC)[reply]

" It is soaked for a short period..."

Soaked in what?

IceDragon64 (talk) 21:28, 9 November 2014 (UTC)[reply]

I am no metalurgist,, but I believe that the article contains a lot of bits and pieces which are really only about annealing iron and steel, mixed into the sections as if they might apply generally to annealing. Most obviously the graph, which is surely only about ferrous stuff, but doesn't clearly say so. This is a general article about metal annealing and these things should be clear.IceDragon64 (talk) 22:23, 9 November 2014 (UTC)[reply]

Without reading the articles, the initial sentence here and at the dab page should include Annealing (glass) within its SCOPE and they should be merged. Are the processes and effects actually different? or is the current fork of material about improving-durability-of-common-materials-through-adjusting-temperature-during-their-initial-construction just a mistake? If so, the two pages should be merged and placed at Annealing as its PRIMARYTOPIC. The EB, e.g., treats these both as an identical process with a single article. — LlywelynII 03:39, 22 June 2015 (UTC)[reply]

• "Without reading the articles,"

I'll just leave that here. Andy Dingley (talk) 09:56, 22 June 2015 (UTC)[reply]

• Oppose. The processes seem different. I don't see grains and work hardening being topics for glass. Glrx (talk) 03:48, 25 June 2015 (UTC)[reply]

• I would agree with the merging of these two articles, i.e. Annealing in Metallurgy and in Glasswork under one article that could be named Annealing (Industry). The processes and results are similar enough to be treated under one article as different paragraphs. There is also annealing in gemmology as a treatment of heavily included gemstones. Once again, the process and the result are similar. OK to merge. 203.161.10.36 (talk) 23:50, 30 June 2015 (UTC)[reply]

• Is this a joke??? It makes as much sense as merging Quantum annealing and Annealing (biology) because of commonality of title. Gemmology? Sure, if you want an article dealing with the risks and rewards of annealing gems, fine, but that too would belong either in its own article, or in Gemmology. EB started as a paper product, so a single article might have suited them, but that does not imply that a single article is a good idea for WP, or even that EB didn't make a hash of it that we thankfully can avoid. Before repeating any such suggestion kindly DO read the articles and ensure that you understand just what the two topics have in common and how they differ, otherwise you might equally well argue for merging Wagon and Aircraft on the grounds that they both are means of transport. The improving-durability-of-common-materials-through-adjusting-temperature-during-their-initial-construction theme doesn't even notionally apply to the different types of annealing, and to the extent that it might, you might equally well include cooking in the merge. The various types of annealing are applied in different ways to different materials, different objects and for different, wildly divergent purposes. To suggest that either the processes or results resemble, not only suggests ignorance, but lack of understanding. That there are certain common concepts is true, but those are abstract, unhelpful in dealing with the material topics, and, if anywhere, they belong in a set index article to replace the current disambiguation article, not in a single-article mish-mash of distinct topics with mainly disjoints sets of readers. JonRichfield (talk) 16:22, 8 March 2016 (UTC)[reply]

• Agree, though reserved: A read of the glass annealing process doesn't refer to any elements of that process which would be unique from in metallurgy - the glass specific facts would be fitting under a heading there. Not to say there are not further differences that a more detailed article here would uncover... but until this article was made more detailed it doesn't justify itself.

Also worth considering, 'annealed glass' is (at least in Australia,e.g. in the National Construction Code / Building Code of Australia) a specific term in building construction. It may make more sense to have a single 'annealing' article, and a completely separate one for 'annealed glass'. 14.2.15.60 (talk) 09:48, 5 April 2016 (UTC)[reply]

• Oppose. I read both articles, trying to better understand the original concept of annealing in order to explain the computer algorithm of simulated annealing. To my lay eye, they are completely different and should remain separate pages. Ma^t_chups 21:16, 20 May 2016 (UTC)[reply]

• As there's clearly no support for this after a year, I've removed the tags. Andy Dingley (talk) 12:08, 5 July 2016 (UTC)[reply]

For historical treatment, the EB9 and EB11 articles (which treat the metal and glass treatments together as a single article) are at

• "Annealing" , Encyclopædia Britannica, 9th ed., Vol. II, New York: Charles Scribner's Sons, 1878, p. 63–64.
• "Annealing, Hardening, and Tempering" ,
  Cambridge
  : Cambridge University Press, 1911, p. 70–72.

 — LlywelynII 03:39, 22 June 2015 (UTC)[reply]

Annealing in biology is where Hydrogen bonding is created. Nothing on this page or any other page about that 2001:8003:6A23:2C00:BC63:CAFB:AD3B:D3CF (talk) 04:24, 16 October 2018 (UTC)[reply]

The third paragraph in the introduction says "In the case of ferrous metals, such as steel, annealing is performed by heating the material (generally until glowing) for a while and then slowly letting it cool to room temperature in still air. Copper, silver and brass can be either cooled slowly in air, or quickly by quenching in water. In this fashion, the metal is softened..."

...that paragraph reads as if quenching is an integral part of the annealing process (is it?) and as if the quenching causes the metal to be softened, where my understanding is that quenching does the opposite. Could someone knowledgeable clarify or re-phrase?

Chconnor (talk) 00:17, 20 June 2021 (UTC)[reply]

At the risk of being too philosophical: Language in the Thermodynamics section seems to ascribe mechanistic causality in a complex physical system to simple and abstract mathematical constructs:

 "The creation of lattice vacancies is governed by the Arrhenius equation, and the migration/diffusion of lattice vacancies are governed by Fick's laws of diffusion."

Creation and movement of lattice vacancies are complex processes, involving nearest-neighbor quantum mechanical effects, grain-sized collective effects, and others at scales between and beyond. While these processes can be fairly accurately described, modeled, predicted, compared etc. by the two named equations, suggesting that a complex physical system is somehow controlled by a simple equation is a bit suspect. See, e.g., these two quotes in ^[1]

   "How can it be that mathematics, being after all a product of human thought which is independent of experience, is so admirably appropriate to the objects of reality? [...] In my opinion the answer to this question is, briefly, this: As far as the laws of mathematics refer to reality, they are not certain; and as far as they are certain, they do not refer to reality."
   — Albert Einstein

   "Physics is mathematical not because we know so much about the physical world, but because we know so little; it is only its mathematical properties that we can discover."
   — Bertrand Russell

Cteno (talk) 14:43, 18 November 2021 (UTC)[reply]

An editor has identified a potential problem with the redirect Stress relieving and has thus listed it for discussion. This discussion will occur at Wikipedia:Redirects for discussion/Log/2022 June 8#Stress relieving until a consensus is reached, and readers of this page are welcome to contribute to the discussion. Wallby (talk) 07:47, 8 June 2022 (UTC)[reply]