Forging v grinding.

In general it is same idea - stock removale use preforged steel and whyle forging they do repetitive heat treatment...

However, it is possible to increase carbon content in different parts of the blade in forge using different technic - as smith did old days, so you may consider this as an manual or more sophisticated heat treatment...

In the old swords which were investigated in modern lab they find different hardness as well as different carbon content in different part of the blade - not randomly spread but intentionaly:
http://www.damask.nm.ru/Lib/teh10.html
Sorry it is in Russian.

Thanks, Vassili.
 
Good thoughts Vassilli:
All stock removal blades are not equal, nor are all forged blades equal, to consider them in two distinct groups is doing the individuals who make them a disservice.

Many of the blades of yesterday knew true greatness, you did them honor by bringing up what many have never been exposed to.
 
However, it is possible to increase carbon content in different parts of the blade in forge using different technic - as smith did old days, so you may consider this as an manual or more sophisticated heat treatment.

As a stock removal maker you can ask for this from the manufacturer in the form of laminates. Note that much of the techniques like that were due to restrictions on steels, it is hard to argue such is necessary now with the very high quality and very inxpensive steels available. We really don't need as much to be so concerned about steel that we have to forge weld steel to wrought iron.


-Cliff
 
As a stock removal maker you can ask for this from the manufacturer in the form of laminates. Note that much of the techniques like that were due to restrictions on steels, it is hard to argue such is necessary now with the very high quality and very inxpensive steels available. We really don't need as much to be so concerned about steel that we have to forge weld steel to wrought iron.


-Cliff

It is not about welding different types of steel, but about heating it in carbon rich enviroment, like in dark part of the flame where surfase may gain some carbon or in bright part of flame where it loose carbon. Or something else - my point is that in old time smith manage to manipulate carbon content and grain size in different part of blade as well as temper it differently.

We may call forging again - manual heat treatment or something. If you read Achim Wirtz article about wootz - he sad that during thermocycling carbodes migrate and form microstructures inside blaed, so temperaure there is exactely temperature used for forging and so not because of mechanical impact but because of heating-cooling during forging it may gain similar to wootz properties.

Like D2 is pretty close to wootz in composition, it already had some Vanadium in right amount and already has diffusive heat treatment in the plant. So if you forge it you may actually end up with blade similar to wootz - with same microstructures.

Again, I think it is not as simple as it may looks like.

Thanks, Vassili.
 
It is not about welding different types of steel ...

I was using that as an example of a technique used for similar reasons that you would case harden mild steel for example. Yes you can add carbon or take it out of steel by forging but no one would argue that would be superior to actual ingot steels given modern manufacturing methods.

... in old time smith manage to manipulate carbon content and grain size in different part of blade as well as temper it differently.

Yes and my point was that this isn't necessary usually with what is available in modern steels, not to the extent that hammer forging does it anyway.


...so temperaure there is exactely temperature used for forging and so not because of mechanical impact but because of heating-cooling during forging it may gain similar to wootz properties.

If you want to talk about themo-cycling then a stock removal maker can do that just as easily. However again, in general, this isn't going to enhance the steel significantly because if it would then the steel manufacturer would be doing it (and they are actually, they just stop at the point they think is optimal). Note segregations such as found in wootz are generally not a good thing. P/M is specifically designed to prevent carbide segregation. If you take such a steel and cycle it so you segregate the alloy and enlarge the grain structure in certain areas then it would be hard to argue it was improved. Cashen's has argued the best you can do with hammer forging is not damage the steel and it takes several cycles of normalizing to even out the grain and refine it to get the steel back to the state it was delivered in when it was in bar stock.

Quite frankly, most of what is stated about forging are just claims with no actual support. Often times comparisons are unequal such as stock removal vs forged with different heat treatments, or comparison methods too subjective (stop cutting when the knife loses "bite") with no actual controls to remove user bias. Have you ever, even one, seen anyone who claims forging is inhernetly superior have a direct comparison of their knife vs an optimal stock removal knife which was made by another maker so you could see the best of both being compared.

-Cliff
 
Zone tempering is what used a lot on top custom blades till now. So there is some benefit in having different part of the blade treated differentely. Of course is steel with same hardness shows superior toughness - no reason to do this, but it is not the case yet.

And if increasing carbon content increases hardness and decrese toughness then there is a basis to manipulate this to create optimal blade tough but with best edge.

...Note segregations such as found in wootz are generally not a good thing...

It is not 100% prooven yet. Not all crbide sub structures known yet for modern science and nobodu really know what is going on - what chemestry is in melted steel. According to Ivan Kirpichev who doing his experiments the way he melted steel is very important and produce different results with same composition. I mean he vary only temperature procedure while his bulat is in melted state and has different results.

Does this already known by modern metallurgy? It focused on homogeniuse steel and get rid of all carbide segregation because do not know how to manage, how to manipulate how to make it benefit steel.

I hear some miraculas stories about what Ce (Zeriy?) can do in small quantities to high carbon steel - because it enforse somehow carbide segregations.

So I still think that this is not yet clearified and there are more questions then answers here.

Thanks, Vassili.
 
It is not about welding different types of steel, but about heating it in carbon rich enviroment, like in dark part of the flame where surfase may gain some carbon or in bright part of flame where it loose carbon. Or something else - my point is that in old time smith manage to manipulate carbon content ...

Forgive my butting in, but this caught my attention. Vasilli, this sounds like you may be familiar with it in more than an anecdotal manner, have you personally done this? I have been very interested for some time to get details from a credible source on such techniques actually producing effects as striking and measurable as the claims present. Could you recommend any old texts that described that the smiths intentionally did what we see in the old blades and how they did it?
 
I got my impression that this is not a simple question from this website (but this is only what I am only certain in):

http://www.kuznec.com/stat.htm

This smith actually do a lot of testing and he looks honest - he was pretty enthusiastic about damascus initially but after a lot of testing he does not consider it as a performer...

So he is doing his researches.

Plus some other random sources - like that link I already provided whee there is clear indication that sword has different structure in different part.

And Bulat (wootz) is very interesting topic for me and I try to support it on my website.

http://playground.sun.com/~vasya/Achim_rus.html

But do not expect from me being smith myself, sorry - I am more like a book worm.

Thanks, Vassili.
 
About 10 years ago Rex found a translation of some work done in Russia in the 60's I believe, the work was very comprhensive. They were light years ahead of any work done in this country. He sent me a copy, I will try and find it.
The work you cited by Achim is right on track.
 
There is no doubt that one can find differential structures in many old swords, that is a firm starting point for all of us. What I am looking for is the original references, not modern studies, that would allow us to say they definitely did something intentionally with a specific set of techniques, more so than wishful extrapolation of some of the magical descriptions in the old sagas. Obviously there are no smiths or witness's that are 500 years old so the best we can hope for is that the smith recorded his intentions and techniques to achieve them in written form. A text from the 1960's, while quite informative in a thorough modern analysis of the materials themselves, would offer nothing in determining the thoughts and intentions of the original smiths.

It is much easier to equalize carbon and even remove it in a forge that it is to put it into the steel, indeed if one looks at tatara production methods and conditions present in bloomery production through the direct process, it is much easier, and more likely, to add carbon in the bloomery process and then refine the levels later. The prevalence and success of this method among the Japanese would support this idea.

Intentional grain refinement is a simple thing to accomplish in a forge, or any other heat source for that matter, but the appearance of differential grain size in blades of shallow hardening steel is more quickly explained by the formation of finer grained products of hardening versus coarser grained structures from unhardened material, as evidenced most vividly once again in the blades from Japan. Features not requiring a forge or hammer to produce.

I believe the original focus of this thread was the possible differences between materials that have been forged and those that have been ground. It is very common for these discussions to get quickly sidetracked into totally irrelevant topics such as wootz. It is probably so common because it is so effective in misdirection. Wootz is made in a crucible, not a forge, and while patterning and refinement was historically done with a hammer, what makes it distinctly wootz is the carbon levels and distribution imparted solely by heat in the crucible. With a hammer one then breaks up the segregation just enough to make it usable, pretty much the same as any poured steel before it is ground or forged by us. And it is also worth remembering that the pattern by which wootz is most recognized can be erased and recreated at will by sufficient heat in the total absence of a hammer.

As an observer I personally think it would be more interesting to have more of the original topic addressed and have a separate discussion on the unrelated characteristics of wootz.

But do not expect from me being smith myself, sorry - I am more like a book worm.
This is no problem at all, I myself am a bit more of a bookworm than a bladesmith, I only use the bladesmithing to reinforce and fill in the gaps that many books have, but those gaps are much less problematic than the wild assumptions made by too many smiths.

http://www.kuznec.com/stat.htm
thank you for the link I will have a close look at it myself.
 
How about simply visiting the motivation of the smiths. When Nobels fought with honor, they expected greatness of their weapons. When one broke, if the nobel survived the smith was put to death.

It was all about survival.
 
How about simply visiting the motivation of the smiths. When Nobels fought with honor, they expected greatness of their weapons. When one broke, if the nobel survived the smith was put to death.

What?

Ed, I'm very curious to know your source for this. Are we talking about a specific culture and time frame here? (Not sure how you're using the term "nobel")

If the smith's primary motivation were to make an unbreakable sword at any cost, and his own life also depended on that, I should think we'd see a lot more swords that resemble 10 pound crowbars. Most designs I can think of could indeed be broken if abused.
 
I will search for the story. Could it have been Shakespare or one of his contemporaries? I was in high school when I first encountered the thoughs, Maybe Gibbon in the Rise and fall of the Roman Empire? In the same venue, the cross bow was declared to lack honor as a weapon both for the weapon but the man who used one.
The swords and other weapons were at one time the weapons of mass destruction, their development top secret. The best were made by the best, scerets meant wealth and longevity to those who knew. One article spoke about an apprentice or slave who tested the temperature of the quench tank and suffered greatly for seeking this knowledge, as I remember his punishment was death.

This held true until conscripts and the common man came to fight battles for the elite, then mass production took over.

I imagine some of the elite still sought greatness in their weapons, as they still do today, but the potential for most of them to come to the test in battle is remote.
 
I recall a similar article about a Japanese swordsmith from a different school who tested the temperature of the quench water, and had his hand cut off as a result...

I am not well versed in the history of the Roman empire, but I should think they would be an outstanding example of "mass production" regarding weapons. So are we talking about stuff from even earlier? (Maybe we should be discussing forging vs. casting if we want to delve into the bronze age. :) )

Regardless, it seems like we're getting a bit off track again. On the topic of forging vs. grinding, for modern blades made out of modern steels, I'm not yet convinced there either method is directly superior.
 
Individuals be it a company of many or one man, make knives, the more complete control they have over their materials the greater their ability to achieve. It does not matter where or when. Success comes from devotion, control, elbow grease and intelligence. That some in history were great can be communicated through their product. Their tribute out lives them and inspires others in the future.

The only way you will know which is superior is to test for yourself doing what you want a knife to do.
 
Initial questin was about buying forged knife or made by stock removal and answer is

- "It shjould be done by skilled custom maker who testing his knives"

Saying that do not by forged knives as well as saying do not by knives made by stock removal both wrong. Stock removal blades are preforged on the plant - they are kind of forged already as well as forged knives may have same heat treatment as one made by stock removal or even more sophisticated (depends on master) because I consider forging as manula, custom heat treatment. So there is no direct and simple answer.

This is my point.

Thanks, Vassili.
 
Initial questin was about buying forged knife or made by stock removal and answer is

- "It shjould be done by skilled custom maker who testing his knives"

Saying that do not by forged knives as well as saying do not by knives made by stock removal both wrong. Stock removal blades are preforged on the plant - they are kind of forged already as well as forged knives may have same heat treatment as one made by stock removal or even more sophisticated (depends on master) because I consider forging as manula, custom heat treatment. So there is no direct and simple answer.

This is my point.

Thanks, Vassili.

And a very good point it is:thumbup: .
 
Actually no I won't, I am not enough of a book worm to read many other languages yet:( , in that area I can only be envious of your abilities Vassili.

I hope this may help:

http://babelfish.altavista.com/babelfish/trurl_pagecontent?lp=ru_en&url=http://www.kuznec.com

It does not always work so I did it by copy-paste here http://babelfish.altavista.com/

Auto translation of Victor Kuznetsov article http://www.kuznec.com/svarka.htm

"As everybody knows carbon burns down made of steel with the force welding. So after the first welding its quantity decreases by 0.3%, and each following welding reduces the carbon content in the packet by 0,1%. These numbers gave L.B.Arkhangel'skiy of 6 years ago in the journal "metallurgist", then A.Mar'yanko into "cut" finally I.Kulikov in the "blade", after adding that "no one nothing of new about Damask steel now writes, only they copy and is repeated each other". Thus, the fact of carbon depletion was authoritatively proven. Is especially convincing was convincing the analysis of contemporary Damask steel, in which C=0.6%, although it is clear that spring (S=0.65%) least carbonaceous component of these Damask steel, and steel U -8; SHKH-YSHCH and file do have S=0.8-1,2%. where they did disappear these percentages? - they burnt out. Old Damask steel are not entered in this iridescent picture: three-layered Damask steel from great Novgorod, XVv. Novgorodians even somehow can be explained: welding only by one, steel took U -19A (not worse), is a little burned-out, that was remained it was sufficient so that we would hesitate in thought. So V.Basov it wrote, "that most highly carbonaceous Damask steel, which it cooked, had S=1,4% and it does not have a concept, as is obtained Novgorod Damask steel S=1.7%". As so! I understand - them saved ignorance of language and distance from the world center of blacksmith craft. If they would know, they read, then even they would not undertake their they were rolled. I put itself in their place, completely I forget about the achievements, progress, authorities - in the memory there remains only truism, known to each blacksmith from the generation: flame in the furnace consists of two parts. Lower part - oxidizing, with the surplus of oxygen; upper part - reducing - with the surplus of carbon monoxide. I get accustomed to this flame. Yes really here bright, white point as from the electro-welding, to eyes it is painful to look - precisely in it I always heated packet for the welding, and higher than it - yellow zone with the soot. In it even does not be desirable to place the metal, in - the first it is clear that it will not be heated, but even if it is heated, then indeed is slow, but the time of money. Nevertheless - experiment requires victims. To Beer the spring, I place into the zone of reducing flame and I await. I await already 20 minutes, it were heated to the dark yellow color, nothing it occurs, then suddenly it begins to be fused on the passage to the light yellow, as stearin spark plug and by drops it drips on the bottom of tuyere - there are no sparks in the mention. I pull out spring, look, the smooth fused surface of clean gold color. Analysis to carbon: S=1,9%. The spark from this film is yellow, is short, downy as in steel (in cast iron - long and red). This film is very thin, some microns and more thickly it does not become, is how much not Grey, since its constant fusion occurs and the runoff (photo of this film see in the gallery on www.kuznec.com). I simultaneously voice the assumption that gold ebb on the Damascus steel - this determined % of carbon. Thus appeared the thought to conduct welding in the reducing flame. Experience the first: for the ease of calculation I take one steel: 9KHS. I gather five developments on the metal into the packet and make 16 weldings, approximately 10000 it is layer. Analysis showed: (to look figure) the experience of the second: Two developments from U -1Д precise analysis U -1Д: (to look figure) after by the 7th of the weldings: (to look figure) small increase in carbon speaks about the small number of weldings. It is still small factual material in order to assert accurately, and approximately already it is possible to say that every 7 weldings increase the carbon content in the packet by 0,1%. I assert that it is possible to create "Damascus" - as steel with the properties it is higher than in source materials, but not the mixture of steels with burnt out carbon and low working qualities. Carburizer consists of the mixture of sawdust from under the emery and cast iron. This mixture is fused into alloy steel having S=1,2%-1,5%. Certainly, composition depends on that, who on this emery process what steel. In me the collection of steels is such: U -1А, U -1Д, KHF-SHCH, 9KHS, 9KHFM, 8Kh', 'Kh". It is understandable that sawdust - these are oxides: carbon of sgorel, master alloy remained, but they are restored by cast iron and seams are obtained white, dense, carbonaceous. Flux I use high-temperature. For this into borax we add common salt and ground bottle glass. Only green. It will approach from the beer bottle, but it is better to take in the green bottle of fault "Carmenere" or "Sira", the productions of Chile - to my taste - are better in the world (true, not cheaper than 12 uyey for the bottle). However, this is theme for another periodical. So here, high-temperature flux does not flow even with the white luminescence of metal, if proportions are correctly selected. Which to make sufficiently easily is purely visual: if flux is too liquid - add still salt and glass, if it is dryish and is not melted, then augers and glass. The forging with 1300t looks like caramel and will not sparkle with this flux, i.e., oxygen does not penetrate it even on the anvil. We boil thoroughly 7-20 times, packet is ready for the forging. It is possible to forge, but personally I still attempt to convert into the Damascus steel, i.e., nagrevayu to 1300t I leave in coals until the morning - let it be it crystallized, as he wants. Next day the forging occurs at a temperature not above 950t, but the final removal of outlines occurs with 700t. hardening usual: 800-.830t into oil t=90-200. One additional problem simultaneously was decided: the welding-in of high-carbon steel into the low-carbon. In order to weld these two began together, them usually tyuey nagrevayut to different temperatures: low-carbon to 1300t, and highly carbonaceous to 1150-.1200t, they connect on the anvil and forge. Thus, for instance, welds on blade to the axe. But this is single-time welding, and for obtaining Damask steel do be required 5-20 weldings with 1300t (otherwise low-carbon steel they are not welded) that to make, if it is high - carbonaceous, alloy steels with 1200t are destroyed? It turned out that they are destroyed, if we attempt ourselves to weld them immediately, in flight, and after several weldings with t=1150 and forgings it becomes trained to high temperatures, more thermo-durable and is maintained welding at the end of the process. To mean, before welding U -1Д in the spring, it it is necessary to anneal and to forge, or to make first 3-4 weldings itself with itself, and then to cook. Secondary special features of this welding method: disappears effektnost', by something to astonish the spectators: there is no roaring fan, there is no furious- white glow of forging, does not flutter on the smithy liquid cast iron - everything appears as usual forging. So that is necessary to select, between the spectacular transformation they became into iron and the calm creation of Damask steel. The second: the furnance loss of metal because of low temperatures and flux decreases - output is more. I drew the conclusion that enemies in force welding two: oxygen and uneven heating, but in no way reduced temperature. In the zone of oxidizing flame these enemies are strong: oxygen penetrates all slots, and uneven heating consists in the fact that the surface of packet already burns, and the temperature inside an even insufficient for the welding. Placing the packet scarcely higher - into the reducing flame, we of these two enemies get rid: there is no surplus of oxygen, and slow heating guarantees the uniformity of the warming up of entire packet. I await the confirmation of results from the brothers on the reason and the anvil. Since the article was written in 200yag., I want to add that to March 200shchg. welded Damask steel: S=1,8%(of 9 strips U -20A and of 8 strips U -1Д, of 3 weldings) and three-layered Damask steel for 2 weldings: Persian Damascus steel S=1,65%, plus U -1Д, plus is file. I now make the attempts to weld Damask steel S=2,0%, if it comes out, then I will study its qualities for completing the table about the cutting properties of steels."
 
His work appears, quite involved but I must reserve any judgment or comment on it, since any conclusions could only be based on assumptions of his meanings due to the broken and incomplete translation by Bablefish. I have used Bablefish many times in the past and have always been concerned with the amount of mistranslated words.

It does address the subject that caught my attention the most from this thread- the concept of carburizing to any significant levels in a smaller forge fire. Many claims have been made about it over the years and around 90% of them have been faulty, those that appear to actually be possible to even the smallest extent are so involved that it would be infinitely more productive just to start out with good steel to begin with, even in ancient times with the bloomery process as I mentioned previously.

Due to atmospheric conditions and control, decarburization becomes vastly more an issue than attempts at carburization. While forge welding, which appears to be what the author is dealing with, there are indeed different areas of a bottom drafted fire that are more prone to decarburization and any smith, from the dawn of the Iron Age to the present, would do well to learn these areas in order to keep carbon where one wants it. Perhaps we are seeing the same situation but from different directions, for I believe that a smith could easily change carbon levels in a forge by removing carbon without even really trying. I have strong doubts that carbon could be placed at will to selected parts of the blade in any meaningful amounts. Also under conditions where moisture can affect atmosphere, it has been shown that an oxygen rich heat can concentrate carbon on the outer surface of steel, due to the greater affinity that O2 may have for the iron than the carbon, making it appear as if carbon content has increased.
 
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