Talk:Sintering

Ice in water example
As of this writing the page states: "An example of sintering can be observed when ice cubes in a glass of water adhere to each other, which is driven by the temperature difference between the water and the ice." This seems to possibly (likely, to my thinking) contradict the stated definition of sintering which specifies that sintering occurs "without melting [the material] to the point of liquefaction". The ice example already has a citation-needed tag. If you can confirm that ice melting is not an example of sintering, please remove the example. If you can confirm that ice melting is an example of sintering, then please cite your confirming source. Adallace (talk) 22:19, 23 December 2015 (UTC)

Adallace, I agree with you that this is not an example of sintering. The process that causes separate pieces of ice to bond should be an entry in and of itself. Water is actually very poorly understood, this ice example is just a similarity, pointing out that two solid objects are getting fused together for some reason. I looked around for a scholarly article to reference but couldn't find an entry about ice interfaces. Dr. Gerald Pollack has published some great stuff about the 4th phase of water, just in case anybody's interested. --Todluv (talk) 16:17, 22 March 2016 (UTC)

It seemed to me pretty clear that the ice-cubes example was a light and airy metaphor, and that no matter what might be going on at the points of contact between the ice cubes, the whole cubes do not melt. I have therefore removed the copious drive-by tagging. Just a lot of loud distractions for the reader. Adallace's concern is no doubt worthy -- and Talk, not interlinear animadversions -- seems to me the place for that concern.

David Lloyd-Jones (talk) 13:18, 16 August 2016 (UTC)

Just wanted to add that there is a good section on ice skating in the premelting page. As described in that page, the moving water particles are in a quasi-liquid state, which I believe also occurs in solid state sintering (occurs below melting temperatures -- see the ceramic sintering section of this page). Ice cubes fusing into a large block in the freezer over time is probably a more correct (not necessarily better) example of sintering. I don't think the example needs to be updated, but it would be great to clarify the presence of "quasi-liquid" in sintering, e.g. parts of the article that discuss capillary pressure resulting in densification. --Cviu (talk) 02:23, 5 July 2023 (UTC)

Definition
Sintering of powdered metals requires an organic "forming" compound to be mixed with the steel alloy which is pressed in a form, usually in a vacum furnace, at very high heat 2000deg or so, this may vary. The high heat burns out the forming material. Sintered metals then require a traditional heat treating process, since the high heat makes the grain structure do some crazy things.

Mergeable information
From the article "sinter":


 * Sinter is a material charged to the Blast Furnace in the Ironmaking Process.


 * It consists of fine iron ore fused at high temperature with fluxes to form a porus clinker, which is later charged to the blast furnace.


 * Sintering takes place in a Sinter Plant, sinter plants are also used to recycle waste material generated elsewhere in the steelmaking process.

This material should be checked out and merged in by someone with more expertise in the field than I. -- 71.48.151.56 01:23, 11 June 2006 (UTC)

Copyvio
I removed the whole section on microwave sintering, as it seems to be a copyright violation. See the original. --Slashme 13:27, 26 September 2007 (UTC)

Frit
What's the difference between fritting and sintering? --Ayacop (talk) 06:36, 29 July 2008 (UTC)

That equation
I don't believe it. It implies that maximally dense iron (D = d) has tensile strength equal to its elastic modulus, which is ridiculous. What's the source for it? -- 99.140.63.214 (talk) 10:37, 3 August 2008 (UTC)

... materials with high melting points such as Teflon and tungsten
Tungsten melts at 3695 K. Teflon has a melting point at around 600 K. Can we really write that Teflon has a high melting point and even compare it to tungsten. I did not edit the sentence myself, because maybe Teflon's melting point can be considered high for the purpose of sintering. Can anyone clarify this matter? --193.40.245.26 (talk) 10:01, 2 February 2009 (UTC)


 * I see where you are coming from, the sentence is poorly worded. However, the point is correct, with the point being that tungsten and teflon cannot be easily manufactured using "standard" processes that are common for either of them. I.e. teflon has a high melting temperature for plastics and tungsten has a high melting point for metals. But again, it really needs to be reworded to remove the ambiguity. Wizard191 (talk) 02:31, 5 February 2009 (UTC)


 * There, I tried to reword it in a less ambiguous way. Let me know what you think. Wizard191 (talk) 16:53, 5 February 2009 (UTC)

Proposed merge from pressureless sintering
Pressureless sintering is a stub that I don't foresee growing too much bigger, so I think it makes sense to merge it into this parent article. Wizard191 (talk) 19:06, 10 September 2009 (UTC)
 * I agree. --John (talk) 22:01, 10 September 2009 (UTC)

General Sintering
I changed (p0)2/3 and (p0)1/3 to (p0)2/3 and (p0)2/3, because I assumed that was meant to be a subscript 0, indicating the initial state; p0 evaluates to 1 and is a meaningless statement. Note that I'm still not sure exactly what quantity p0 is supposed to represent, though. The source cited immediately after is a book, so I can't readily check. 131.151.66.22 (talk) 03:47, 18 November 2010 (UTC)

Snow sintering
Sintering is the mechanism that allows powder snow to be packed. Compressing snow and waiting for it to sinter is part of building a quinzhee. Source. I didn't see a good place to put this, but it should be covered here. Jokestress (talk) 09:06, 9 January 2013 (UTC)

sintering nylon?
Hi,

what is about sintering nylon as 3d printing material. could there be a section about that in this article? — Preceding unsigned comment added by 91.17.204.163 (talk) 21:09, 31 July 2016 (UTC)

Definition - third sentence
The third sentence makes very little sense: "The nanoparticles in the sintered material diffuse across the boundaries of the particles, fusing the particles together and creating a solid piece."

"The nanoparticles" - the definite article implies some (nano) particles have been referenced, thus this is unclear.

No, nanoparticles do not diffuse. Atoms or molecules diffuse.

Even if they did, how would that fuse the particles together?

I know the general sentiment is sound, but to define the process needs a much more accurate and clear early sentence. 98.209.55.221 (talk) 17:44, 13 June 2024 (UTC)