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Freddy1

Jun 4 2008, 06:08 PM

Does anyone know if ancient Chinese swords makers have ever temper & folded swords like how they do it with Japanese swords (maybe not as sophisticated)? Like folding hard and soft metal layers together.

I'm just wondering how sophisticated the metalurgy of Chinese swords in general. I have heard of chrome plating of Chinese swords.

btw If you have any pictures that would be great.

General_Zhaoyun

Jun 4 2008, 09:01 PM

The following sites contain some info and pictures on the metallurgy of chinese swords:

http://thomaschen.freewebspace.com/photo3.html
http://chineseswords.freewebspace.com/about.html

Yang Zongbao

Jun 4 2008, 09:33 PM

QUOTE (Freddy1 @ Jun 4 2008, 06:08 PM)

Yep, the Chinese did temper and fold their swords, especially the early ones. Indeed, the Japanese got their swordmaking techniques from China and Korea (which in turn got them from China). Chinese swords are as sophisticated as those by the Japanese, but the Japanese have a history of making the art itself into something sacred, where in China these things tended to be but professions.

Chen06

Jun 5 2008, 12:19 PM

That and the fact that Hollywood and the media has made the Japanese Katana and Samurai seem like some kind of uber-invicible warrior and weapon combo ( though those who have read history know that is not true). Chinese and Korean swords are just as good as Japanese swords but they dont get the exposure so no one really knows about them. The way things are presented can really change ones perception about a certain thing - in this case, Western/Hollywood's obsession with equating Samurai with uber-invicible warriors and katanas as divine blades that can cut through everything and are superior to any other swords. Anime and the spreading of other Japanese pop culture has also helped

Kenneth

Jun 5 2008, 09:22 PM

QUOTE (Freddy1 @ Jun 4 2008, 06:08 PM)

Hi Freddy,
chroming of swords is a myth that won't die. Elemental chromium could not be plated on metal by ancient peoples. The modern technique (which is only a modern technique) uses electicity to distribute chromium on the surface.
The Qin long swords of bronze, in which context the myth is often repeated, used pottasium chromate which is quite different and was applied to the surface by a boiling in a solution. This means the surface layer has a small % of elemental chromium but not anything to qualifying a chroming nor was it effective in stopping corrosion on many of the treated weapons. Many Qin swords have visible corrosion if you examine enough pictures and look past the shiny ones.
Some pictures and explanation here:
http://www.chinahistoryforum.com/index.php?showtopic=17605

A more common technique was tin plating, which was used for pattern decoration, or to form a silvery tin layer. High tin layers also resist corrosion better than normal copper-bronze. Such bronzes look 'chromed' (silver) but are tin. The Qin swords are neither however.
Swords with either tin plating or high tin percentages (in excess of 15%) are fairly common in the late Eastern Zhou period. Such weapons could be made much sharper than a usual bronze with lower tin%.

Yes, the Chinese folded steel (initially the East Zhou folded iron was more a low-carbon steel). Chinese worked metal long before the Japanese, who were still in the Neolithic period untill both bronze and iron reached Japan during the Zhou period. The craft of sword making in Japan can be traced to China.
Different types of steel were made by different processes, but a true mid-carbon steel & highly refined blades existed in the Han period...long before the katana appeared.
Unfortunately this is another traditional craft that has been ignored in China while it was preserved in Japan. Just like some Koreans maintain Ming-era horse archery some Japanese maintain the craft of making swords via traditional means. It should not be forgotten where it began, nor what China seems to have forgotten or neglected over the 20th century.

A good book to read would be Yang Hong's "Weapons in Ancient China", or publications by Donald Wagner on iron & steel in China of which he has several on the internet.

Here is an extract from my article on Bronze ge, the section dealing with metallurgy;
{pictures not uploaded...sorry. Lazy. This is a draft, I will supply a Pdf. of the article when I get around to finishing it}

Iron & Bronze metallurgy. pp.43-46.
For a period covering centuries both iron weapons and bronze weapons co-existed within China. While bronze casting almost certainly emerged as a locally developed technology from Neolithic experiments there is compelling evidence that iron working was introduced to China via central Asia & the steppes [55]. Meteoric iron was worked in the Bronze Age Shang dynasty & Western Zhou period which can be identified as extraterrestrial due to its high nickel content (Yang 1992.) Such heavenly iron was worked into blades that were fashioned onto bronze axes & dagger-axes. The true Iron Age does not begin in China until the Eastern Zhou period. Figure 72 shows a bi-metallic weapon of this earlier period. Both meteoric and apparently imported smelted iron was found at Sanmenxia in Henan. Dated to the 7th century BC at the earliest it shows how heavenly iron may have created an interest in steel.
---------------------------------------------------------------------------------------------------------------------- 55) Donald Wagner: ‘The Earliest Use of Iron in China’. 1999.

Figure 72: Bronze dagger-axe with iron blade. Late West Zhou/early Spring & Autumn period.

The earliest wrought iron objects in peripheral China are found in the modern area of Xinjiang province, with a conservative dating to the 8th century BC but possibly earlier. Qin state (on the western flanks of ancient China) has some of the earliest securely dated iron objects within the Zhou sphere, dated to the 6th century BC. These were luxury items, including elaborate short swords with lost wax cast gold hilts.

Figure 73: Qin iron dagger with gold hilt with turquoise inlay. Spring & Autumn period.

The form of some of the curved knives in these Qin graves suggests a possible steppe connection (Wagner 1999) while the conspicuous use of gold also suggests an influence of these nomads (Michaelson 2007). It should be remembered however that despite the presence of iron in these Spring & Autumn period Qin graves that bronze weapons were still used by Qin state to defeat the other Warring States, even those armed with iron, at the end of the 3rd century BC. These earliest iron objects were exotic trappings. Testing of one short sword showed the iron to have 0% carbon, hence softer than bronze. Bronze was therefore not physically inferior to the earliest wrought iron weapons. From a beginning as a luxury object, perhaps a substitute for prestigious meteoric iron, the technology slowly filtered through China. Even at the close of the Eastern Zhou however iron was not yet ready to replace bronze Testing on iron weapons of the late Eastern Zhou shows that weapons were annealed in such a way that it produced quite a soft microstructure for a steel, and not better than a good bronze. The mechanical properties of such wrought iron was not qualitatively superior to bronze [56] This explains why such early steel weapons were used alongside more typical bronze ge without simply outclassing them.
Iron technology was initially better placed to revolutionise the production of farm implements rather than supercede bronze weapons. The ancient Chinese pioneered the production of cast iron agricultural tools. The casting of iron implements was only possible because of the high temperature cupola furnaces unique within ancient China. The invention of cast iron is presently attributed to the south of China, specifically state of Wu (Wagner 1993) which had less access to copper deposits than other states. These tools were of cast white iron, very high in carbon conent, which means a very hard object, but also brittle. Such iron was unsuitable for weapons, hence benefited a farm economy but not a military. Cast white iron was a cheaper alternative to bronze tools. Once iron was known to Chinese it is perhaps not surprising the expertise of bronze casting would lead to experiments with cast iron, or that extremely effective furnaces might lead to the accidental discovery of cast iron.
-----------------------------------------------------------------------------------------------------------------------56) Donald Wagner: ‘Iron & Steel in Ancient China’. 1993.

The very high temperatures required to cast iron were not available in other iron working cultures, who instead worked with hammering sponge iron, or blooms, in a pasty state to form tools or weapons. Initially it was wrought iron, made in this fashion, which entered China from Western frontiers. Even after many centuries the level of adoption of an iron industry as a complete alternative to bronze was quite uneven across the various competing states (Yang 1992.). In the Warring States period certain states are mentioned in the histories as wielding good iron weapons or wearing iron armour, but weapons alone did not decide a victor and they were extinguished nonetheless. Even amongst those states there is always a certain amount of bronze weapons found alongside in modern excavations. Chinese did not have the same background expertise in wrought metallurgy compared to their thousand years of fine bronze casting. This is likely why both Eastern & Western bronze & iron working developed in two different general directions: The West used annealing technology on cast bronze while the Chinese used casting technology on smelted iron. In the Eastern Zhou period the ability to create a liquid iron allowed new techniques, such as puddling liquid iron and stirring it (stir-fried steel) to remove impurities from the iron to make steel, but the quantities produced were still small. Most weapons excavated in a mass grave of Yan soldiers showed the weapons to be a folded wrought iron rather than folded mid-carbon steel. The steel industry was still in its infancy (Yang 1992). Analysis shows the uneven carbon content between annealed layers. Technology has improved dramatically by the era of '100 time forged' (true steel) weapons of the Han iron industry. The soldiers armed with iron weapons in the late Warring States period did not have iron weapons that were physically going to outclass bronze. One positive aspect, as mentioned earlier, is that these iron swords could easily be made longer the bronze swords. The long bronze swords that appear in the Qin Buried Army then are likely mimicking or competing with long iron swords of rival states like Yan. I am not convinced that such high tin bronzes were a good material for making long slender swords however. When Chu state graves contain iron swords as long as 1.4m there would have been some pressure on bronze casters to at least match such intimidating blades. 90cm bronze swords in the Buried Army were found with general and officer figures. Ge rather than such swords were the common soldiers weapon. Only in the Han period was there industrial output of highly refined weapons-grade steel. A technique for producing a wrought iron straight from the blast furnace was developed. At the end of the Han era there was even true mid-carbon steel being produced by blending pig iron & wrought iron directly within a furnace. While Chinese appear to have borrowed iron technology from the West they then developed the material into previously unheard of ways by using Chinese technology and ingenuity. The peculiarities of Chinese metallurgy, the use of ultra-high temperature furnaces which led to fine casting & multi-sectional molds, may also explain 2 features of Chinese bronze weapons: Typically high tin % in weapons, and a lack of evidence for work hardening of their edges. The Chinese weapons for which I have figures for put these bronzes in the upper limits of what is practical for a weapon. A tin % above 15% is a very hard bronze but more prone to break rather than compress or deform. A 20% tin bronze may have a very sharp edge, but will be brittle. In the West there was 'work hardening' of blade edges which allowed for sharper and harder edges than the base alloy would possess. This required skill in just the right amount of cold & hot annealing but a well hardened edge had significant benefits and could be worked wafer thin. Chinese seem to have abandoned experiments with wrought bronze from the earliest period and concentrated on casting, while developing a uniquely sophisticated industry they then missed this technique. High tin % bronze were instead used for sharp edged weapons. The unique Chinese solution to the problem of combining durability/tensile strength with a hard edge was the manufacture of bi-metallic bronze swords. Such swords were being made by the YuYue in the early 5th century BC but are comparatively rare due to the extra effort in production compared to the quantities of sword needed to be supplied for war. Bronze swords, even more so than ge, have a surprisingly high tin % based on a small amount of analysis available. Some swords approach 20% tin. The hue on other swords I have seen suggests to me there a variance between standard bronze & high tin bronze, but Chinese did push the limits of practicalities with their higher tin % swords. While red copper-bronze swords exist other swords have a distinctive silvery high tin appearance. It appears some of these are just tinned blades, with normal copper-bronze underneath. This may only be an aesthetic surface layer since a true bi-metallic is more complex. The unique Chinese bi-metallic sword of the Bronze Age was a copper-bronze spine & hilt with a separate casting of the edges onto the weapon which thereby avoided the risk of breakage.
A normal copper bronze is more likely to take stresses without breaking, but the blade could not be sharpened so fine, this higher tin% edge meant a keener blade. By avoiding a high tin % spine in the bi-metallic Chinese sword of this type had the best features of both. The katana for instance was made over 1,500 years after this date but its fame is based around a similar principle, a low carbon steel inner spine with tensile strength with a higher carbon harder out edge. In destructive tests with a modern (10% tin) bronze sword severe stress deformed (i.e bent) but did not break the blade. A higher tin % sword is more likely to crack. This was the challenge that bronze casters of weapons worked with. The apparent omission of work-hardening in China would seem to be a symptom of the unique properties of Chinese technology. Another reason that made work hardening less likely to be exploited by Chinese artisans is the presence of both lead & high tin % in ancient weapons. Since Chinese made very fine castings lead was almost standard in the alloy. It meant the liquid bronze flowed much better through a mold but it also meant a softer bronze (Bavarian 2005.) Lead reduces the effectiveness of cold working a blade edge compared to a non lead-bronze. A high tin % may make harder bronzes but made work hardening even more difficult, with cold working impossible in the upper tin % that Chinese swords & dagger-axes are often attributed [57]. “The exclusive use of casting by the early Chinese metalworkers may have been due to the poor malleability of these alloys”. (Bavarian & Reiner 2006.) There was however clear understanding of the different types of bronze produced by different volumes of lead or tin. By the Spring & Autumn period a document called the ‘Artifactors Record’ had a section on “Six Formulas of the State of Qi” which gave the ratio of tin & copper for bronze bells & tripods, mirrors, swords, ge & ji, axes & arrowheads (Yang 1992). The ratio however does not seem to fit what we know about ancient bronze as there is rather less evidence of control and also the figures of 20-25% tin for ge & ji or 25-33% tin for swords beggars belief. This exceeds a more reasonable 5-15% for bronze and creates instead a brittle ‘white bronze’. The given ratio should not be taken as gospel, nor the percentage calculated from it. It is unclear whether the ratios meant pure tin & copper each, or an alloy with lead already included. Yang Hong uses both interpretations in his chart, hence the % range, but even the lowest range appears too high. The Artifactors Record reveals knowledge over the value of a given alloy, but does not present a practical composition. The lower results appear as much a 10% too high on average.
In the production of weapons the alloy was crucial. This is why the much greater attention paid to analysis of ancient bronzes through the study of ritual vessels would seem to offer less insight into the nature of the bronze casters craft and their control over composition of a bronze. Bronze vessel can have huge variations on the percentage of lead or tin, by tens of a %, and even with a large base sample it has not been possible to make conclusions, such as dating a vessel by its compositional analysis (Bagley 1977). Unlike the huge variance of bronze vessels it has been shown, in general support of the Artifactors Record, that certain types of object are generally clustered under a certain type of bronze alloy (Bavarian & Reiner 2006). High tin % bronze mirrors (white bronze) where created due to the ability of a white bronze to have a fine polish and its reflective qualities. The very high lead % of Yan state knife-money may either be due to the colour of the bronze produced (‘grey’) or simply that a lead bronze may have been cheaper to use as a currency. The Artifactors Record fails as a universal standard for anticipating a bronze composition; as well it should given the long history of bronze casting, the many disparate centres of productions, and material facts over supply & availability/control of the components of bronze. There is also reason to believe bronzes were re-cycled and hence the caster may not always known, nor may it have been important, of the precise proportions.
Weapons however are quite different given their function as a life or death tool that must take the stress of striking bone, or another weapon, or hard surface. Empirical knowledge of a bronze alloy & its qualities would be crucial. The very small amount of accessible material on ancient Chinese weapons analysis is a regrettable fact. A rather small sample specifically on ge & ji is available through the English language publication of Yang Hong (Y), 2 ge with analysis in the Shanghai museum (SM), and one independent analysis* (see below) which I have combined here.
object Copper% Tin% Lead%
West Zhou ge (Y) 82.72 13.61 0.78
West Zhou ge (Y) 87.44 10.75 0.1
West Zhou ge (Y) 73.38 12.1 12.41
West Zhou ji (Y) 85.42 12.84 0.26
West Zhou ge (Y) 84.31 11.65 0
Warring states ge (SM) 79.61 15.57 3.4
Warring States ge (SM) 80.74 18.09 0.17
Warring States ge* [58] 83.57 15.53 0.02
Some notable variance is visible even within this small sample. The higher tin % of the Warring States ge may suggest attempt to push the limits of sharp edged and hard bronzes at that time. The % of lead varies from a tin-bronze of 0% lead to another with 12% lead. This 12% lead ge would have a much softer edge than the former. While these are not quite as skewed towards a high tin % as the similarly small sample of tested bronze swords I am aware of it does confirm a trend of >10% tin in dagger-axes. These weapons would be capable of holding a sharper cutting edge but at the same time were more likely to chip or break instead of compact an edge or deform through critical stress. Other elements in the alloy of >1% I have not included as these are normally impurities of an ore rather than a product of an artisan, although certain ores may have been favoured. In closing I will discuss on another aspect of the testing of the dagger-axe which comes as a result of authentication. On the table above the Warring States dagger-axe marked “*” is from an unpublished analysis which was done at the same time as metallurgical examination of the internal corrosion along with C14 dating of the remains of a shaft which belonged to this weapon. The actual weapon was a ji halberd, and it also had a bronze zun mounted on the same pole. The remains of the shaft are shown here before the commencement of a preservation process (figure 74).
--------------------------------------------------------------------------------------------------------------------- 57) Jeroen Zuiderwijk: Personal correspondence 58) Melanie Roy: personal correspondence. EPMA testing by Oxford Materials Characterization Services.

Anthrophobia

Jun 5 2008, 10:34 PM

QUOTE

The form of some of the curved knives in these Qin graves suggests a possible steppe connection (Wagner 1999) while the conspicuous use of gold also suggests an influence of these nomads (Michaelson 2007). It should be remembered however that despite the presence of iron in these Spring & Autumn period Qin graves that bronze weapons were still used by Qin state to defeat the other Warring States, even those armed with iron, at the end of the 3rd century BC. These earliest iron objects were exotic trappings. Testing of one short sword showed the iron to have 0% carbon, hence softer than bronze. Bronze was therefore not physically inferior to the earliest wrought iron weapons. From a beginning as a luxury object, perhaps a substitute for prestigious meteoric iron, the technology slowly filtered through China. Even at the close of the Eastern Zhou however iron was not yet ready to replace bronze Testing on iron weapons of the late Eastern Zhou shows that weapons were annealed in such a way that it produced quite a soft microstructure for a steel, and not better than a good bronze. The mechanical properties of such wrought iron was not qualitatively superior to bronze [56] This explains why such early steel weapons were used alongside more typical bronze ge without simply outclassing them.
Iron technology was initially better placed to revolutionise the production of farm implements rather than supercede bronze weapons. The ancient Chinese pioneered the production of cast iron agricultural tools. The casting of iron implements was only possible because of the high temperature cupola furnaces unique within ancient China. The invention of cast iron is presently attributed to the south of China, specifically state of Wu (Wagner 1993) which had less access to copper deposits than other states. These tools were of cast white iron, very high in carbon conent, which means a very hard object, but also brittle. Such iron was unsuitable for weapons, hence benefited a farm economy but not a military. Cast white iron was a cheaper alternative to bronze tools. Once iron was known to Chinese it is perhaps not surprising the expertise of bronze casting would lead to experiments with cast iron, or that extremely effective furnaces might lead to the accidental discovery of cast iron.
-----------------------------------------------------------------------------------------------------------------------56) Donald Wagner: ‘Iron & Steel in Ancient China’. 1993.

I was wondering on the problem provided by this context. If iron was of the same quality as bronze during this period, why did it replace farm tools but not weapons? Is it become farming tools needed to be more malleable than weapons, considering bronze is harder and thus less durable than iron? And if early iron had the same quality as "good bronze", then logically wouldn't it still outcompete bronze considering the cheaper cost? It's hard to imagine why anyone would suffer the resources to make good bronze weapons when they could have the same quality iron weapons at a cheaper cost. Or could it be that it would take too much economic effort to replace all bronze factories with iron ones? I hope Yang or Donald mentioned something about it, because all of mine are just personal guesses.

btw, welcome back, I feared you've left forever!

Kenneth

Jun 10 2008, 04:17 PM

QUOTE (Anthrophobia @ Jun 5 2008, 09:34 PM)

That's a lot of questions Anthro but I believe each one was answered in the actual passage.
Iron was not the same quality as bronze, there are different qualities for each.
There was no parity in 'quality' between ancient iron and bronze. The different types of 'steel' depend on the nature they are produced and the best steels only become common in the Han period.
The cast iron used in farm implements was white-iron, which is brittle but hard.
This white-iron could not be used for weapons. Cast iron was developed in China, supposedly around the state of Wu (although there may be changes from more investigation). This is due to the lack of copper deposits in the region so an alternative was sought. The state of Wu still used weapons of bronze.
In contrast to Wu state iron deposits are rare in Yunnan, and copper was plentiful (and tin and lead was exported in ancient times).
The reverse was true here, and we have bronze cultures thriving during the West Han period, hence the bronze hilted iron bladed swords of 'Dian' and other ethnicities. Iron was rarer than bronze in that area.
This is perhaps one reason iron technology was uneven in ancient China during the WS period. The earliest iron was not simply better than bronze (although a forged iron sword could be made longer than a cast bronze one) and while some states worked the 'new' material into weapons, other did not.
The quality of early 'steel' (remember, the material for weapons was a different iron/carbon% to the farm tools) needed to improve before it was able to outclass bronze. Bronze lingered for a long time in China for this reason.
Iron weapons are roughly 10% lighter than bronze weapons, so as soon as good steel could be consistently made then bronze was economically and qualitatively inferior to steel. In the late East Zhou this was not yet the case.
The decline of bronze weapons in the Han period is quite swift for this reason.

Nighthawk

Jun 14 2008, 08:01 PM

Sorry for reactivate this post. But I have some Questions.

How flexible was the typical chinese sword in the 13th century? Was it flexible like a today Tai chi- sword (sorry don´t know the real name of these sweord type) or was it more like the the typical european swords?

Why I ask is that I try to find out if a chinese swordsman with top level skill (of course he have to be a top level martial art fighter

) have the posibillity to found a way into a european plate with the blade.

Thanks.

Yang Zongbao

Jun 14 2008, 09:47 PM

QUOTE (Nighthawk @ Jun 14 2008, 08:01 PM)

) have the posibillity to found a way into a european plate with the blade.

Thanks.

Hello Nighthawk,

Real Chinese swords are actually not as flexible as the movies would have you believe. They shouldn't bend beyond a very slight flex.

The proper term for a two edged sword is "Jian", which means sword. For single edged blades, the term "Dao", or Saber, is used.

For more information, you can also try browsing www.swordforum.com , they have some good people to ask on swords.

Nighthawk

Jun 24 2008, 12:24 PM

QUOTE (Yang Zongbao @ Jun 14 2008, 09:47 PM)

Thanks for this information Zongbao

DaMo

Jun 25 2008, 11:47 AM

The sword of King Gou Jian of Yue (about whom I will be watching TV series this summer

) definitely deserves mention in a thread such as this. One of the best preserved ones from the Spring and Autumn period, it is composed of different alloy proportion in different parts. Most significantly, the core is softer than the blade, allowing it to retain a sharp cutting edge while keeping it less brittle as a whole.

josh stout

Jul 10 2008, 01:10 PM

QUOTE (Nighthawk @ Jun 14 2008, 09:01 PM)

) have the posibillity to found a way into a european plate with the blade.

Thanks.

I am not well versed on the strength of plate armor, but it seems that European swords designed to deal with armor were two handed, and large enough to damage the armor itself even if the edge did not cut through. A jian would never be used this way, but there were many Chinese two handed dao/pole arm type weapons that could have been used in a similar fashion to European two handed swords. A thick, well tempered blade used in a two handed fashion could damage armor with a bludgeoning chop. The jian was not designed for such crushing chops. Nevertheless, jian technique does include methods for dealing with armor. Many of the techniques are designed to deal with Chinese lamellar armor, such as thrusting upward at an angle to pierce between overlapping rows. Other techniques exploit the gaps and weak points that any armor must have, such as under the arm.

No antique jian I have encountered has been flexible in the manner of modern wushu toys, but there is a great variation in blade thickness. Some would make very effective cutting weapons, while others have thinner blades more appropriate for thrusting and slashing. The jian during the Qing dynasty was not considered a battlefield weapon, but many heavy, plain examples exist that clearly were not weapons for duels between scholars. Often these village made jian are short cutting weapons with heavy iron pommels. They are general purpose weapons that could have been used effectively in a close press of bodies as well as in a more sophisticated fencing situation. Some, with typical heat treated high carbon edges, are thick and tip heavy enough that they might cut plate, but that was certainly not what they were designed for.
Josh

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