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From the article: "A couple of decades ago, Toyota researched on producing a ceramic engine which can run at a temperature of over 6000°."
How many decades ago, and is that 6000°C or 6000°F? Kind of important. Bryan Derksen
Has to be 6000°F. 6000°C is up to solar temperatures. Edited to include the F. Don't know any more about it, although 6000F is still incredably high. I can only find a couple of materials with a melting point in that range or higher (tungsten (6010F), Diamond (6240F) and Hafnium carbide (6940F)). Even with HfC (which, might I add, I've never actaully heard of being used anywhere), that's stil close to the melting point, it would have to have pretty serious mechanical properties at that temp to be usable (not unknown, nickel superalloys can be used up to about 30°C from it's melting point, but damn rare), particularly considering that it's got to contain the explosions. Plus, to run an engine at over 6000°F your talking about buringing something exotic like oxy-acetalyne, or possible hydrolox. My suspicion is that the engine is a petrol engine made of ceramics that have a melting point over 6000°F, and not that it can run over 6000°F. Granted, my experience is in the electrical ceramics, and not the structural, so I'm going to leave it in, pending research. Syntax 05:13, 23 Jan 2004 (UTC)
Right, bit of a major update there. Notable points:
1) My spelling sucks. Plus, I tend to the British spellings.
2) Traditional cermaic crafts are over at pottery. MatSci ceramics are here. Anyone forsee any problems with that?
3) I've tried to pitch the entry at the right level. Please holler if something is unclear - I'm too used to writing technical stuff on this.
4) Did I mention my spelling sucks?
An interesting article but I cannot understand why it has been included under handicrafts. More appropriately it should be under science of materials. I think the author is also puzzled by this classification.
Pottery is also known as ceramics. It is simply that one word has an Old English origin and the other a Latinate origin. They both used to refer to the same craft/product and have done so for many centuries. See the OED.
People working as artists with clay may choose to be known as potters, ceramists, ceramic artists, ceramicists or clay workers. Those who choose to identify as potters usually produce work that can be used in some way as well as appreciated for its intrinsic beauty. Potters also make one-off pieces. Nonetheless they may still choose to identify as potters. I suggest you refer to William Morris, Bernard Leach, Soetsu Yanagi and the Mingei movement in Japan which will give a philosophical background to this choice.
Ceramic artists may either be people who have trained in ceramics, acquiring skills in both the making and designing of art works in clay (which may well be referential to the long and rich history of ceramics) or they can be artists like Grayson Perry who simply choose clay as one of several media in which they work. There is also a growing tendency to place ceramists under visual arts and design rather than art or pottery.
I would suggest to the editors that there be entries under both categories (pottery and visual arts and design). Maybe artists/potters and their work could be listed under visual arts and design and practical/technical information under pottery with cross-referencing to each. Karen Weiss
negative resistance
These are devices that exhibit the unusual property of negative resistance. Once the voltage across the device reaches a certain threshold, there is a breakdown of the electrical structure in the vicinity of the grain boundaries, which results in its electrical resistance dropping from several mega-ohms down to a few hundred.
This confuses me. I understand that, as explained at negative resistance, negative resistance can be taken to mean merely that current is a decreasing function of voltage in a particular region of the current-voltage curve. But the above doesn't describe that. In fact it describes a situation where current in increasing greater than linearly with voltage. So if these materials really have negative resistance, the above does not describe their behavior. Josh Cherry 01:52, 25 Jun 2004 (UTC)
Or maybe I'm just confused. Does a given voltage actually have two possible values of voltage in some regions for these devices, with slopes of opposite signs? Josh Cherry 02:14, 25 Jun 2004 (UTC)
You're quite right, the resistance drops sharply at high voltage, but the resistance (both V/I and dV/dI) remains positive.
That is confusing. The device you refer to is called a varistor, for variable resistor. A varistor has a change in resistance when it is subject to relative high voltage to its device rating. The term variable is misleading. Once the arrester is hit with high voltages its performance continue to degreed and it is irreversible.
The basis of an arrester, and this would make a good article is to fail like a fuse, but not on the same principle of a fuse, and protect its more expensive part. These arresters are also termed lightning arresters fail when there is lightning nearby. They normally fail as 99% or more when there is a lightning direct hit. The part it is protecting is also often destroyed.
Anyway, a ceramic component called an MOV Block, also called Metal Oxide Varistor (Variable Resistor). Ceramics such Zinc Oxide, Cobalt Oxide, and other oxide ceramics are manufactured though a ceramic process (see Ceramic Engineering).
After the blocks are manufactured and put into a surge arrester the arrester has as a kV value that is directly related to the number of blocks with its own kV value put in a stack. Put simply a 10 kV arrester has three, 3.3 kV blocks.
A 36 kV arrester has 12, 3 kV blocks.
Now going through all that, this industrial part example may explain the confusion.
- A surge in terms of a voltage strike crosses a line. If the voltage is <3000 V and the arrester is a 3 kV arrester. The arrester absorbs the spike, but it "weakens" so the initial resistance has degraded to a new lower resistance, due to the internal rearrangement of the grains. The arrester can withstand spikes over 3000 V, which is over voltage. Again, the durability of the part is unique to each part due to many factors. The over voltage will weaken the part, but may not cause it to fail.
-Not only do spikes cause degradation on an arrester, but also that the arresters are powered up as part of the circuit they are in.
-When the arrester has been hit repeatedly with surges and is in operation over a "long time" as in many years, it degrades to where it no longer arrests spikes, and the equipment it protecting is now subject to degradation. However, their can be a second layer, such as surge redirection to ground. or third layer of protection like a circuit breaker. The arrester is cheap, cost effective, efficient device and effective in protective sensitive parts..
-Note, your surge protecting multi-plug test strip warn that after the a warning signal shows as in it has been hit with a surge, they recommend you repair or replace the unit. There is a good reason for that. The company I worked for made arresters for those very same protection strips.
-As for the phrase of "these devices" I believe what I explained is one example of what the phrase alluded to.
Why have the refractory and elec properties been removed?
I thought the content before 9 March 2005 was quite relevant
Sintering
There's a decent, but incomplete article on sintering that I tried to improve until I saw the excellent section of this article. Perhaps there should be a link and some moving of content?--Joel22:56, 26 May 2005 (UTC)[reply]
Can reach a better separation between the "Fine arts" subject of "Ceramics" and the building material? I have created a new but short page: "Ceramic material" for building stuff. Sorry about the I18N chars corrupt. I am fixing it now. -- Fplay23:20, 20 December 2005 (UTC)[reply]
It's more than just "building material". Ceramic materials are used for a lot of different things in engineering. At a glance, this article seems to be entirely about the engineering usage of the term, and not at all about the art form. In your new category scheme, this article, as-is, should be the "main article" for Category:Ceramic materials. Category:Ceramics does not currently have a main article as far as I know.--Srleffler00:38, 21 December 2005 (UTC)[reply]
The following discussion is an archived debate of the proposal. Please do not modify it. Subsequent comments should be made in a new section on the talk page. No further edits should be made to this section.
Oppose as per my comment in discussion. Since "ceramic" is the adjective and "ceramics" is the noun, I'd follow the example of Metallic (adj) redirecting to Metal (noun). If you disagree with my comment in discussion, please do reply and explain why! --Lox (t,c) 14:50, 14 January 2006 (UTC)[reply]
Oppose. "Ceramic" is much more commonly an adjective, and Wikipedia policy discourages page names that are adjectives. "Ceramics" is correctly the singular noun for the art of production of ceramic materials. One can talk about "a ceramic", referring to a type of material, but this usage is not as common as the other two.--Srleffler17:04, 14 January 2006 (UTC)[reply]
SupportCeramic is a category of noun called "collective singular", similar to Plastic, Furniture, Information, etc. While they are indeed singular, we do not use them in the context of "a [something]" but "a piece of [something]" or "an item of [something]." The OED supports this. Ebenbrooks17:27, 16 January 2006 (UTC)[reply]
Support The page isn't about the art of pottery, and there doesn't seem to be any compelling reason to ignore the OED as to usage of "ceramic" as a singular noun.Jamused03:49, 17 January 2006 (UTC)[reply]
Comment, likewise, I see no compelling reason to ignore either the Cambridge dictionary or the Merriam-Webster dictionary. I must admit, I'm slightly bemused that the dictionaries, from my reading, give different impressions. Perhaps someone could check my references and see if they read differently? --Lox (t,c) 08:14, 17 January 2006 (UTC)[reply]
Comment Actually, the Merriam-Webster online says that ceramic as a noun is "plural but singular in construction", in other words it's a collective singular as Ebenbrooks has pointed out. The American Heritage Online agrees with the distinction between "ceramic" the singular noun meaning the material or an object made of ceramic, and "ceramics" the plural noun used with singular verb meaning the art of making objects of ceramic. The Cambridge online dictionary is the Learner's, and presumably incomplete by design. Really, though, it's not a matter of majority rule among the dictionaries; the OED attests to the fact of ceramic used as a singular noun and cites examples going back to 1859. As I read it Wikipedia naming policy favors use of the singular unless the singular form doesn't exist, as with "scissors"; it does not propose a balancing test based on frequency of use, or contributors' sense of their regional dialects.Jamused14:48, 17 January 2006 (UTC)[reply]
Support: ceramic is correct as a collective singular noun, like "cereal". More pragmatically, it simplifies inline linking, since we can always write [[ceramic]]s for the plural. Jonathunder10:32, 17 January 2006 (UTC)[reply]
Discussion
Add any additional comments
Comment
The term "ceramic" is
an adjective describing an object that has been made from clay and baked
The term "ceramics" is a
Singular noun that refers to production of ceramic materials
When you vote, please bear in mind that should choose the word that describes the article best, since this is (in my opinion) not a simple of case of singular / plural nouns --Lox (t,c) 14:46, 14 January 2006 (UTC)[reply]
Hmmm. Sorry, I didn't realise this point of usage. Here in Australia a ceramic (singular noun) is an object made of ceramic (also singular noun). My dictionary agrees with me. This is a bit like sport (British English) vs sports (American English). I'm happy for the proposed move to fail, if this point of usage is noted in the article. (I can add it myself.) -dmmaus10:02, 16 January 2006 (UTC)[reply]
Please check the edit I just made. I think American English also does have 'ceramic' as a noun for a type of ceramic material. e.g. Porcelain is a ceramic. Also, I assume all of the usages except the singular noun for objects made of ceramic are common to both American and Commonwealth English. —The preceding unsigned comment was added bySrleffler (talk • contribs) 13:21, 16 January 2006.
I think the edits that the two of you have made are very good and clear this situation up very well! Thanks for your contributions! --Lox (t,c) 13:58, 16 January 2006 (UTC)[reply]
As I stated in the voting above, Ceramic is, indeed, a singular noun, but of the curious form called "collective singular". Collective singular nouns are nouns that describe either a plurality of objects or an undifferentiated, undefined quantity of something. Other nouns that fit this classification include Pottery, Information, Furniture, Clay, Plastic, and (in some uses) even Paper. The OED supports this use of Ceramic, and even American English uses it quite commonly. If you require citations, I can provide. Ebenbrooks17:34, 16 January 2006 (UTC)[reply]
The above discussion is preserved as an archive of the debate. Please do not modify it. Subsequent comments should be made in a new section on this talk page. No further edits should be made to this section.
Change and reasons
From “Earthenware, which is made from potash, sand, feldspar and clay.”
Why? Because it’s not
To “Earthenware, which is often made from clay, quartz and feldspar.”
Why? Because it is!
Regards,
Andy
Hello all,
I've added an the ASTM definition of ceramics ... or at least ceramc article Regards, Andy
Hello 70.52.112.133
Thank you for your comments but cement is produced by the action of heat on raw materials, and therefore would comply with the listed definition. To quote from the wikipedia entry on Portland cement “ ...and similar materials are made by heating limestone (as source of calcium) with clay or sand (as source of silicon) and grinding the product (clinker), with a source of sulfate (most commonly gypsum). “
As an aside whilst the catergorisation of cement as a ceramic material is agreed by some it is not universal
Regards,
Andy
Hello again 70.52.112.133,
Whilst the final articles, such as concrete blocks, do not require the action of heat the manufacture of cement does, and therefore complies with the listed definition. Please see the wikipedia entry on Portland cement. Should you still not be happy with this please use the talk pages rather than changing the entry
what is ceramic? i want to know...my teacher ask me and friends to do a research on ceramic
Hello 60.52.20.66,
Have you read the article to which these talk pages are attached? It contains a useful definition: “The American Society for Testing and Materials (ASTM) defines a ceramic article as “an article having a glazed or unglazed body of crystalline or partly crystalline structure, or of glass, which body is produced from essentially inorganic, non-metallic substances and either is formed from a molten mass which solidifies on cooling, or is formed and simultaneously or subsequently matured by the action of the heat.” Rememebr if you do use this you need to give a proper citation
Regards,
Andy
Brittle
Hi all,
I've just re-read the article, and thought about "Historically, ceramic products have been hard, porous and brittle." Call me stupid but what ceramics are not hard & brittle?
Regards,
Andy
At room temperature most ceramics are hard and brittle. At elevated temperatures that's not necessarily true--glass for example. 134.84.54.20918:28, 4 January 2007 (UTC)Julia[reply]
Any chance some mention of what ceramin is can be added to the article? I don't know personally, but I have seen it mentioned in various places. Aristoi19:43, 6 December 2006 (UTC)[reply]
Stoke on Trent Museum
Hi Cbdorsett. I don't think it POV to have use the phrase "The finest collection of Staffordshire ceramics in the world" as
It is.
These are the words used by the museum itself, and which is a non-profit, non-commercial organisation that is a globally respected authority. (and one I have no association with!)
Calling something the "finest" is necessarily putting a value judgment on something, and I think it's out of place here, especially since there is a perfectly fine, neutral way to describe the collection. Cbdorsett17:01, 20 February 2007 (UTC)[reply]
Hi Cbdorsett. But by not using the full description readers will not be aware of significance of the collection (and this is surely undisputed) and so may not realise why it is worth listing ThanxTheriac
Good point. Let me suggest that you read Wikipedia's POV policy Wikipedia:Neutral point of view. Then figure out a way to word the description so that it attracts people, without starting off a competition about who's the "finest", "greatest," "most ..." etc. Cbdorsett19:34, 20 February 2007 (UTC)[reply]
An image used in the article, specifically Image:DSCN0126.jpg, has a little bit of a licensing issue. The image was uploaded back when the rules around image uploading were less restrictive. It is presumed that the uploader was willing to license the picture under the GFDL license but was not clear in that regard. As such, the image, while not at risk of deletion, is likely not clearly licensed to allow for free use in any future use of this article. If anyone has an image that can replace this, or can go take one and upload it, it would be best.
IP address keeps adding this reference with no explanation as to which bit of article it refers to?
- Tschegg, C., Ntaflos, Th., Hein, I., 2008. Thermally triggered two-stage reaction of carbonates and clay during ceramic firing - a case study on Bronze Age Cypriot ceramics. Applied Clay Science (in press).
I have been sorting out the caramics categories, adding new ones such as Category:French pottery and Category:Ceramics manufacturers of the United States and clearing out the vast number of articles on potters etc lazily dumped in Category:Pottery in particular. User:119.224.22.238 has objected to, and twice reverted, a number of removals from Category:Ceramics, without giving any reasoning - he says (my talk):" Thank you for the message. I do not understand your reasoning for your sudden and unilateral changes to long standing categories, my argument for restoration is based on maintaining the status quo until consensus is reached. I would be happy with slimmed down categories but this needs to be by agreement with the community. Therefore I will revert pending discussion and agreement. Regards. ". I had already referred him to WP:OCAT, and said (his talk): "There is no point in duplicating every article in Category:Pottery in Category:Ceramics. I moved many articles into the ceramics materials & pottery categories, and removed most of the duplication where the articles seemed concerned exclusively with pottery. Some of these might be debatable, but you have reverted many where it clearly is not, so I will revert all or most of your changes. Please produce reasoned arguments for further changes." For example he has restored Bird stump (is a variety of vase popular in 1920's England...) to Category:Ceramics, when I had moved it to Category:English pottery. I would welcome comments on this. Johnbod (talk) 14:58, 28 December 2008 (UTC)[reply]
Congratulations on starting this Herculean task. It is not made easier by the disputes between editors on the meaning of "ceramics" and "pottery" and the difference between them.
My own view is that the head category should be Category:Ceramics, which should have two sub-classes, (1) Category:Ceramic materials, including all manufactures other than the making of pottery, and (2) Category:Pottery, which should include both (2:1) useful objects made out of clay and similar materials and (2:2) arts which use clay (i.e., various forms of ceramic sculpture). This is fairly arbitrary, because the Oxford English Dictionary records that "ceramics" and "pottery" are used to mean the same thing, but classification has to be more or less arbitrary.
Within Category:Pottery can go categories for pottery by place, by type, by period and by process. I'm not too familiar with the structure of categories, but it would be most useful if a sub-category could be permitted to appear in more than one higher category if that is helpful (e.g. Faience can be categorised by the place where it is made and what it is made of).
I can't say anything about ceramic materials because that is outside my field of expertise.
As to which category an article should be put into, surely it is logical to put it into the lowest applicable in a hierarchy of categories, since it thereby falls automatically into every category above.
That is very much my view. There are some (about 20) articles which I think should remain in the main ceramics category, as straddling industrial uses & pottery. I have also taken "materials" rather literally & not moved the few bios of scientists from cat "ceramics". There is also Category:Porcelain of course, which additionally complicates matters, plus the manufacturers are in Category:Ceramics manufacturers - I haven't moved those without a by country sub-category from pottery, though perhaps I should. I also think the very lightly populated "ceramicist" categories should be merged or renamed as "potters", which they all seem to be. I hadn't moved Faience, though Egyptian faience, which I added to pottery & the Ancient Roman pottery category, removing it from Ceramics, has been readded there, as one of the reverts mentioned above. There are a number of other articles on different types of faience, & I wouldn't myself add the main article to say "English pottery", though I don't have very strong views on this. Johnbod (talk) 18:23, 28 December 2008 (UTC)[reply]
Hello Johnbod and Marshall46. Thank you for starting the discussion which, as I posted earlier, was my wish. I do not object to a reorganisation but I do believe this should follow discussion. I think my position is not that different that of you both, though I hope you do not object to a few comments in response to some of the above:
In any hierarchy on these subjects "ceramics" must be first and without equal. This is because the primary group that includes all the others, including pottery. All others would be subgroups of this primary whole.
A definition of "ceramics" would be easy to reference as there are professional bodies that haved agreed such. "Pottery" is less precisely defined but there are still viable definitions.
I am broadly in agreement with the above editor. (As you have already shown yourself to be an active editor, you would help other editors if you logged on with a user name.) My only reservation concerns definitions by professional bodies. Professionals in any given field tend to make prescriptive definitions, ruling how technical terms ought to be used. For Wikipedia the descriptive definitions of dictionaries, which report how words are used, are better. I prefer the Oxford English Dictionary (which is now online). We have had a great deal of trouble in the field of ceramics and pottery from editors who want to make prescriptive alternations to common usage.
I agree that the appropriate category for people who make vessels and other useful objects out of clay ought to be Category:Potters But how do you classify artists in clay like Carol McNicholl, who was trained as a fine artist and is essentially a sculptor in clay? She is not simply a fine artist, to be excluded from Category:Potters altogether, because she once designed a range of pottery for the Next store, but she is not a potter, she is a ceramicist. Marshall46 (talk) 10:41, 29 December 2008 (UTC)[reply]
Hello. Thank you for continuing the discussion and the broad agreement, and as for defintions:
You mentioned the OED before advising it suggested that "ceramics" and "pottery" are the same. With the greatest respect to both you and that esteemed publication that is not correct. "Pottery" is a subgroup of "ceramics", whereas the latter is very large group. (it includes much that no one would classify as pottery, for example titanium carbide. This is discussed in the ceramic article of which this is the discussion page. In this "pottery" is described under the whiteware ceramics.)
There are defintions recognised across the world, and from respected and unquestionably authoritative organisations such as the ASTM and The Insitute of Ceramics (now part of IoM3 [[1]])
Is there any defintion, let alone one from a respected body for ceramicist, or ceramist which is another term that some times gets used?
As for the description you give of Carol McNicholl. Designing a range of Pottery for Next would suggest she be categorised as a "designer". Conversely, she could be categorised as a "sculptor." Alternatively she could be categorised as both.
That is precisely what I mean. You dissent from the descriptive definition given by the OED, which records usage, and prefer the prescriptive definitions of professional bodies, which you say are "correct". I don't think you quite grasp the difference between words and things or the nature of definition. What you say is so similar to what an anonymous editor has said in similar discussions elsewhere that I wonder whether you aren't the same editor. If you logged in with a user name it would make discussion easier.
The OED and other dictionaries record how words are used. I accept the authority of the OED in lexicography and so I am satisfied that they accurately record common usage. If "pottery" and "ceramics" are used more or less interchangeably, then it is correct to say that the words mean more or less the same thing. Wikipedia is not the place to make a case for using common words differently from the way that most people use them. (Technical words are different matter.)
I agree that a potter does more than make things out of clay. I also agree that Category:Pottery ought to be a subset of Category:Ceramics.
"Ceramicist" (alternatively "ceramist") is a word used for artists who work in clay. Some potters would also call themselves ceramicists and some ceramicists would also call themselves potters. The relationship between the two is shown in the Venn diagram on the right. You may dislike the word "ceramicist", and I don't much like it either, but it exists, and it is the most appropriate description for some artists.
"which you say are correct." It is not I who say they are correct, rather academic, professional international authorities.
"What you say is so similar to what an anonymous editor has said in similar discussions elsewhere that I wonder whether you aren't the same editor." I do not know to whom you refer. I have not engaged in similar discussions elsewhere, nevertheless this is unsurprising if, as I thinking you are saying, that ceramic and pottery is claimed to be synonymous. (viz - should I write elsewhere that human beings can breath in outer-space it would not unexpected to receive more than one contradictory reply. Would this indicate just one person? Of course not - just a community correcting errors.)
"If pottery and ceramics are used more or less interchangeably" But they are not - I again refer you to the article to which this discussion page is attached.
"Ceramicist" and " but it doesn't matter." What does matter is what this word, or ceramist actually means. I refer to my previous question "Is there any defintion, let alone one from a respected body for ceramicist, or ceramist which is another term that some times gets used?"
"Wikipedia is not the place to make a case for using common words differently from the way that most people use them." I understand the criteria for inclusion in Wikipedia is veritability from recognised authorities. This can be provided for defintion of ceramics and pottery. I am unaware of any such for ceramicist or ceramist.
Without a recognised and accepted defintions both ceramicist & ceramist are unstable neologisms and so must be ignored. Please refer to [2] regarding the avoidance of such words.—Preceding unsigned comment added by 119.224.22.238 (talk) 07:17, 2 January 2009 (UTC)[reply]
Thanks for that correction. I don't know which is more common, "ceramist" or "ceramicist", but it doesn't matter so long as there is a redirect. Is that possible?
