Talk:Differential heat treatment

Unlike makers of Japanese swords, traditional khukuri makers of Nepal and India do not wrap the spine of the blade in clay. They merely pour water down the cutting edge, allowing the residual heat to "heat treat" the blade, drawing brittleness.

Should the article be renamed?
Although I'm still in the middle of working on this article, the question of whether or not there should be two separate articles, (one on hardening and another on tempering), has been nagging me in the back of my mind. Personally, I'm leaning toward "not," because I think it's rather to useful to explain both in one article, which is better for highlighting the similarities and differences between the two techniques. Also, I think perhaps the two together may make a decent sized article. If so, perhaps differential heat treating would be a better title, using the other two a redirects. Differential heat treating is also a commonly used term, which I often see in my sources, but is broader, encompassing both techniques. However, it may also mean including short descriptions of modern versions of these techniques, like flame hardening, induction surface hardening, etc... (Might not be a bad thing.) Any thoughts or suggestions? Zaereth (talk) 19:23, 15 June 2012 (UTC)
 * I agree with the idea. The only thing that bugs me is the -ing form. Hardening, tempering, etc., don't have an easy alternative and are therefore used as nouns, but this is not the case with treating. Thus why not "Differential heat treatment"? This might be a matter of usage, which I can't tell as I normally don't read on this topic. I've just had a brief look in Google Books, and noticed that "differential heat treating" is used well as a noun, but often by non-academic or non-native English writers. Materialscientist (talk) 04:16, 22 June 2012 (UTC)
 * With heat treatment, it could go either way. Adding -ing in this case makes it a noun. Personally, heat treatment is just fine for me. I chose the other version because a while back User:Wizard191 changed the article "Heat treatment" to Heat treating, (for reasons I can't quite remember), so I was using that as a convention. If you prefer, "treatment" is jus fine with me. Zaereth (talk) 04:26, 22 June 2012 (UTC)
 * Done. (It took me forever to find the "move" button.) I hope I did that correctly. I still need to write a new, broader lede, and tidy everything up a bit. I think this article could use some more modern stuff. There is also flame hardening and induction hardening, which I think deserve a short description, along with links to main articles. (Flame hardening is also used in knife making, although it is unsuitable for swords, due to the nature of the heat-affected zone.) Differential tempering is commonly used in manufacturing. For instance, Harvey and Krupp developed a method of differentially tempering steel plate, for battleship armor, back in the late 1800s. Localized tempering is often used on welds, where the entire object may be too large or awkward to heat and stress relieve evenly.Zaereth (talk) 19:22, 25 June 2012 (UTC)

Differential annealing
I notice that differential annealing redirects to this article. This would seem appropriate if it was a metallurgical technique, but I can find no reference to it in those terms. It seems to be used frequently for differential equations, especially in artifical intelligence design. It is also a common term in DNA synthesis, but doesn't seem to be a common heat treating process for metals. It may simply be a misnomer for differential tempering, or possibly hardening. I don't know, but it doen't seem to have any common use in metallurgy. If anyone knows about this term and can add info to this article about it, or can redirect it to the correct article, your help waould be appreciated. Zaereth (talk) 00:40, 30 June 2012 (UTC)

History
The article said: ''Differential hardening techniques were originally developed in China, for making swords, and spread across the far-east, from Nepal to Korea and Japan. Later, methods of surface hardening were developed, by quickly heating in localized areas and then quenching, such as flame hardening and induction hardening. However, differential tempering techniques started with the blacksmiths of Europe, originally for making cutting tools, but was also applied to making knives and European-style broadswords. This process was later used in many forms of manufacture where a combination of strength and toughness (impact resistance) is needed, such as the construction of armor plating in early battleships. ''

I see a lot of claims and little evidence. The one source applies to one fact only. And I doubt that such a history section is useful in the summary. -- Zz (talk) 11:28, 2 August 2013 (UTC)

Reliable Sources
Anything sources that are used to verify the claims made in Wikipedia articles, must be Reliable Sources, as per Wikipeida's policy regarding sources: WP:RS.

Thus the inclusion of things, with the backing of sources that have been demonstrated to be unreliable, or which do not have any citations whatsoever, is not acceptable.--ZarlanTheGreen (talk) 00:15, 25 March 2014 (UTC)


 * Who has determined the sources to be unreliable? Are you able to provide sources which demonstrate that the information provided is false? If you are unable to provide sources showing that the sources provided are unreliable and false, then the information will go back into the article. Zaereth (talk) 02:38, 25 March 2014 (UTC)


 * "Who has determined the sources to be unreliable?"
 * I did ...and I explained the reasons for every removal, in my edit summaries. Is there anything about it, that you did not understand or agree with? ...or did you perhaps not read the summaries?
 * "Are you able to provide sources which demonstrate that the information provided is false?"
 * Irrelevant.
 * "If you are unable to provide sources showing that the sources provided are unreliable and false, then the information will go back into the article."
 * Nonsense. I only need to show that the sources are unreliable OR false. If the sources are unreliable, then they do not qualify as valid sources. Thus the statements do not verified, and have thus no place on Wikipedia. If the statements are false... again: they have no place on Wikipedia.
 * I have no need, nor obligation, to do both.


 * Your insistence that a source which is not a WP:Reliable source, still counts as being supporting a statement, and needs to be disproven for it to be removed, is not in keeping with Wikipedia policy and it is an example of shifting the burden of evidence. You are essentially making an argument from ignorance (i.e. "it's true, unless you can prove otherwise" ...whereas you actually can't say it's true, unless you can demonstrate that it is)--ZarlanTheGreen (talk) 02:50, 25 March 2014 (UTC)


 * TheN, by all means, show us that. Do you expect us to simply take your word for it? If you have any knowledge or expertise, as you so seem to want us to believe, then please show us something other than your own personal opinions on the matter. Zaereth (talk) 02:57, 25 March 2014 (UTC)


 * "TheN, by all means, show us that."
 * Us? What do you mean by "us"? You are the only one who questions my edits.
 * As to evidence... It'll get a bit long so I'll put it at the end.
 * "If you have any knowledge or expertise, as you so seem to want us to believe"
 * I have never claimed to have any expertise. As to claiming to have knowledge... I've done so in informal chats on your user talk page. I have never claimed that what I write or remove, from a Wikipedia article, should be accepted due to any level of knowledge, or "authority" that I might have. This would be an invalid reason, arrogant and completely against the rules of Wikipedia, so I would never do so.
 * Please stop talking about irrelevant issues.
 * "then please show us something other than your own personal opinions on the matter."
 * My "personal opinion"!? I've pretty much never talked about by personal opinion (and when I have, I've made it clear that it was merely my opinion). I've talked about what I've heard/read from qualified experts/authorities! That is neither personal, nor mere opinion.


 * Now on to the evidence that the statements are not verified by reliable sources:
 * "Straight swords, such as ninjato, are often curved the wrong way before heating so that they straighten when quenched."
 * This lacks any source, whatsoever. To quote WP:V: "Any material that needs a source but does not have one may be removed."
 * "Edge on edge blocks with a katana can result in the formation of a large crack and a line for it to follow, causing the sword to break, and can be very dangerous to the sword wielder. "
 * This book is made by the founder and the former head of Nakamura-ryū and is about swordsmanship according to the teachings of Nakamura-ryū. The book itself is quite clear about this being the case (Amazon lets you preview a few pages of the book, so I checked the Foreword and Introduction. They were clear that the book was about Nakamura-ryū, rather than Japanese swordsmanship in general). If you read the Nakamura-ryū article (or any other source, especially from the Nakamura-ryū school itself) you will know that this is a very modern and unorthodox style, which is thus not representative of Japanese swordsmanship (certainly not of traditional swordsmanship). A google search of the book doesn't really give a lot of results and almost all of the results are book-stores, Amazon's page on it has only seven reviews of it, most of which are from practitioners of Nakamura-ryū...
 * "Samurai warriors of Japan were trained to block and parry with the sides of their swords, to protect the cutting edge. "
 * Please read Nick Evangelista or his biography on Amazon (which seems to be written by himself). Sure he's engaged in olympic fencing and classical fencing, but that is not relevant to Japanese swordsmanship, in any way. He has no qualifications in the subject of Japanese sword use.
 * As to the Book of Five Rings... I've looked through it and there is never any mention of what part of the sword you parry/block with.
 * "However, in combat with hacking-type swords, like broadswords, such an extremely hard edge is not always desirable, as blocking and parrying is often done with the edge. With these swords, it is generally desirable to have a more impact-resistant edge, even at the expense of the ability to hold that edge. The edge may need to be tempered to dark-straw or more to achieve this, and the center tempered to a blue or purple color. This leaves very little difference between the edge and the center, and the benefits of this method, over tempering the sword evenly (through tempering), may not be very substantial. However, a sword tempered in this way can usually be resharpened many times, and, although the hardness will decrease with each sharpening, the reduction in hardness will usually not be noticeable until a large amount of steel has been removed. "
 * The first reference is "Knife Talk II: The High Performance Blade By Ed Fowler – Krause Publications 2003 p. 115"
 * As I said in the edit summary: Swords are not knives.
 * The second reference does not talk about any "hacking-type swords", nor does it talk about "broadswords".--ZarlanTheGreen (talk) 04:06, 25 March 2014 (UTC)


 * 1.) I am fine with the removal of the sentence about ninjato. There was no source supporting it, and in all of your edits, I missed that one. When many small edits are performed, it's simpler just to do a blanket revert, but sometimes things get missed.


 * 2.) You obviously have not read the source. Your opinions about whether the particular school is a good one or not are irrelevant. Here is a quote from the source:


 * "With these swords, we tested the effects on the blade of cutting through copper, forged iron, pig iron, and dried bamboo; and of striking to the back, the side, and the cutting edge of the blade while it was secured to a pedestal.


 * "In the blade-on blade experiments, sparks flew from the katana used to make the cut and a deep crack was cut into the one receiving the blow.


 * "It is very clear that blocking a cut on the edge of a blade in the kumitachi practice is very dangerous, and receiving it at a horizontal angle could even threaten the practitioner's life."


 * 3.) Your opinions of nick Evangelista are also irrelevant. If you bothered to read the sources you would see that Mr. Evangelista actually did his research. It is not necessary for an author to be, say ... an atomic physicist to research the subject and write a comprehensive book on it.


 * 4.) Have you read the Mr. Miyamoto's book in its original language? If so, are you qualified to translate it? On page 202 it says "The verb I translated as "slap" is haru';: it is connected with hariuke'', "a parry effectuated by slapping with the flat of the sword."


 * 5.) Just because someone forges knives doesn't make them unqualified to forge a sword, nor to write about it.


 * I can easily locate more sources. Your solution is simple. All that you need to do is find a source that recommends blocking and parrying with the edge, and we can adjust the text accordingly. Lacking that, we (the Wikipedia community that is also watching)cannot simply accept your word that the sources are full of crap. Zaereth (talk) 05:43, 25 March 2014 (UTC)


 * "I am fine with the removal of the sentence about ninjato. There was no source supporting it, and in all of your edits, I missed that one."
 * I suspected that might be the case. Well, as that was a mistake and it's been acknowledged as unsupported and fine to remove, that's fine.
 * "You obviously have not read the source."
 * How would that be relevant?
 * "Your opinions about whether the particular school is a good one or not are irrelevant."
 * ...and neither is yours. The opinions of the founder of the style, is also invalid, as he would naturally be heavily biased.
 * Furthermore, I never said anything concerning how good or bad Nakamura-ryū is.
 * More importantly: The quality of the style is completely irrelevant.
 * What is relevant, is that it does not represent Japanese swordsmanship, in general, and especially not Japanese swordsmanship in feudal times. Not only that, but it is a relatively small and obscure style (and thus coming in conflict with the WP:Undue weight policy).
 * "Your opinions of nick Evangelista are also irrelevant."
 * I did not voice any opinions. I stated facts.
 * "If you bothered to read the sources you would see that Mr. Evangelista actually did his research."
 * What sources, and what research?
 * "It is not necessary for an author to be, say ... an atomic physicist to research the subject and write a comprehensive book on it."
 * Maybe not, but in that case he/she would need to demonstrate that what he/she says is reliable, for it to be counted as reliable information. Say, for example, if he/she had atomic physicists read through the book and vouch for its accuracy.
 * If an atomic physicist writes a book on atomic physics, that counts as a reliable source, unless evidence shows otherwise. Why? Because his degree in atomic physics makes him count as, probably, reliable.
 * If a layman writes a book on atomic physics, that does not count as a reliable source, unless evidence shows otherwise. Why? Because there is nothing to show that the person is qualified or knowledgeable, unless other reliable sources can confirm it.
 * "Have you read the Mr. Miyamoto's book in its original language?"
 * How is that relevant?
 * "If so, are you qualified to translate it?"
 * There are plenty of people who are qualified to translate it.
 * Many have.
 * Thus you need not know Japanese, to have read the book.
 * "On page 202 it says "The verb I translated as "slap" is haru';: it is connected with hariuke, "a parry effectuated by slapping with the flat of the sword.""''
 * That is, of course, a translation note by the translator Tokitsu Kenji, rather than a statement of Miyamoto's.
 * You seem to interpret it as meaning that parries were done with the flat of the blade. I see absolutely no basis for this over-generalization. Just because there existed parries that could be made with the flat, that neither means, nor implies, that all, or most, parries were done with the flat.
 * Furthermore, just because "haru" is connected to "hariuke", doesn't mean that it always (or ever, neccesarily) means the same thing.
 * Furthermore, a word that usually refers to a specific type of parrying, might be used for parrying in general. Words that refer to a specific type of action, have often been used for a more general action, and vice versa. Such is the nature of language.
 * In the quote you cite, there is no clear claim that parries were always, or mostly, done with the flat, and certainly no mention of swordsmen being trained to parry in such a manner.
 * "Just because someone forges knives doesn't make them unqualified to forge a sword, nor to write about it."
 * That is true, but completely irrelevant. I don't really see what point you are trying to make here.
 * Sure, being able to forge knives doesn't make you incapable of forging a sword. How does that demonstrate that they are qualified to talk about swords?
 * "I can easily locate more sources."
 * I rather doubt that you'd be able to easily locate reliable sources, given your track record, but... sure. Locate them, then.
 * "All that you need to do is find a source that recommends blocking and parrying with the edge, and we can adjust the text accordingly."
 * Again: You are shifting the burden of evidence!
 * I have absolutely no obligation to find any such source, for me to remove your claims that they only/mainly parried with the back/flat.
 * Those statements are not verified by any Reliable Sources. Unverified claims can be removed, without impunity. Indeed they are removed with approval of Wikipedia Policy.
 * "that, we (the Wikipedia community that is also watching)cannot simply accept your word that the sources are full of crap."
 * So you claim to speak for the Wikipedia community, do you? You claim to know the opinions of the other editors, do you? You have absolutely no basis for that. With all due respect, that is rather arrogant of you.


 * Furthermore, what is this talk of "that is also watching"? What evidence do you have that anyone has noticed our discussion?
 * None.
 * Sure, there might be hundreds reading this discussion. Or no one. The only time at which we could say that someone else has read any of this, is when they themselves write something, and thus enter the discussion themselves.--ZarlanTheGreen (talk) 22:33, 27 March 2014 (UTC)


 * If anyone prefers a more scientific explanation, just to clarify the types of forces involved, the greater the hardness of a material, the greater it resists wear. Thus, harder materials can hold an edge for a longer time and cut harder materials. The hardness of a typical Katana is around HRc 58-60. In comparison, the hardness of plate glass is around HRc 53. However, steel has higher shear strength than glass. At this hardness, 1065 carbon steel (0.6--0.7% C) has a shear strength of around 165,000 psi. The force of a hard blow from a sword can greatly exceed 4000 psi. That doesn't sound like much, but when you divide it by the actual surface area (I'm being generous at putting it at a ten-thousandth of an inch) you end up with 400,000 pounds of impact force, far exceeding the shear strength of the metal. This allows the sword with higher energy to cut a fairly good distance into the edge before the energy dissipates.


 * Unfortunately, carbon steel at this hardness cannot withstand the shearing forces. (It is this type of hardness that is typically found in scribes or planer blades.) The steel at this hardness also has a high degree of brittleness, which does not allow it to plastically deform to fit the wedge of the blade, so a crack develops. (A good hammer hardness is far better at absorbing impact by deforming to fit wedge, but still has the limits of shear strength. Thus, it can take the deep cuts without cracking, but can't hold an edge as long when cutting hard materials like bone.) Zaereth (talk) 03:02, 27 March 2014 (UTC)


 * None of that is relevant to how we should edit the Differential heat treatment article and is thus not relevant, nor appropriate, to this talk page. Thus I won't bother to reply to it, expect this bit:
 * "The force of a hard blow from a sword can greatly exceed 4000 psi. That doesn't sound like much, but when you divide it by the actual surface area (I'm being generous at putting it at a ten-thousandth of an inch) you end up with 400,000 pounds of impact force, far exceeding the shear strength of the metal."
 * That is speculation. More importantly, it is WP:Original research. Thus it has no place on Wikipedia (well it's okay on a User talk page, where you can chat, but not on any article or article talk page)--ZarlanTheGreen (talk) 22:33, 27 March 2014 (UTC)


 * Are you so sure? Trust me, when I decide to put some metallurgical numbers into the article, I will definitely have sources to back them up. Zaereth (talk) 23:03, 27 March 2014 (UTC)
 * What you wrote there was unsourced (and did not involve any mention, of anything to be included to the article, BTW), so... Yes I am perfectly sure.--ZarlanTheGreen (talk) 23:13, 27 March 2014 (UTC)
 * It is not necessary to source talk page discussions in the way that it is for an article. However, I do remember reading that in one of my sources, which I will dig up for you. If you think no one has ever tested this stuff, I'm pretty sure you are mistaken. Zaereth (talk) 23:52, 27 March 2014 (UTC)
 * Please don't. As it's not relevant to how we should edit the Differential heat treatment article and is thus not relevant, nor appropriate, to this talk page.
 * Please turn your attention to the the actually relevant thread of this discussion (the part that is above your "If anyone prefers a more scientific explanation/.../" comment), instead.--ZarlanTheGreen (talk) 02:45, 28 March 2014 (UTC)
 * Do you have anything to offer except your own personal opinions, because that is what everything you have stated here has been. Anything of substance? Zaereth (talk) 03:12, 28 March 2014 (UTC)