Philosophical Transactions on damascus, wootz & other alloys

kwakster

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While doing some internet research on Sheffield made Crucible Steel, i found some interesting reading material in an old English book named Philosophical Transactions, dated 1822.
Thought you guys might like to read it as well, even though it's in English.

@ Mods: if this post does not belong here please move it to the appropriate subforum.

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Damascus Steel.

The steel of which the beautiful sword blades of Damascus are manufactured, has hitherto baffled all attempts at imitation.
It is generally supposed to be made of slips or thin rods or wires of iron and steel, bound together by iron wire, and then melted together by heat.
The most skilful workmen of other countries have attempted to imitate this process, but in vain; so that there is reason to think that the secret of the manufacture has not yet transpired.
The colour of the Damascus blades is a dull bluish grey, and scarcely exceeds in hardness common steel from the forge.
(It is difficult to bend; and when bent does not resume its shape; the principal character, however, is its water, or a peculiar wavy appearance running from the hilt to the point in narrow lines, the thickness of a harpsicord wire, which never cross each other.
These waving lines arise from a slight difference in the degree of polish occasioned by the unequal action of acid upon the steel; any weak acid would produce this effect, but at Damascus sulphate of alumine is acid.
This appearance of waving lines has been imitated by a false damasking or etching, but the genuine Damascus blade is distinguished from the false one by the obliteration of the lines in grinding, which takes place in the latter.
In the real Damascus blades, grinding nearly removes the water; but it immediately reappears by rubbing the blade with lemon juice.

On Indian Steel or Wootz.

This valuable material has lately been introduced with great success into cutlery.
Sir Joseph Banks was the first person who drew the attention of the public to Wootz, having received it from Dr. Scott of Bombay, and submitted some of it to the trials of skilful workmen so early as 1795.
It is imported in the state of round flat cakes, about five inches in diameter, and an inch thick, each weighing more than two pounds.
The following is the method of making it in India.
Pieces of forged iron and wood are enclosed in a crucible, and heated together in a furnace.
The fire is urged by three or more pair of bellows peculiar to the country.
In this way the wood is charred, and the iron is melted and converted into steel.
It crystallizes in the crucible in the state above mentioned.
According to Mr. Stodart it ought to undergo a second fusion, which should be conducted with the greatest care, and when this is well done, it is so much improved as to be fit for every purpose of fine cutlery, and infinitely superior to the best cast steel of England.
In forging, it requires the utmost attention.
Dr. Scott informed Sir Joseph Banks, that it “cannot bear anything beyond a slight red heat;” for when this happens, part of the mass seems to run, and the whole is lost as if it consisted of metals of different degrees of fusibility.
Mr. Stodart also found that it was useless when overheated, that in hardening it should be quenched at a cherry-red colour, and while tempering, it should be heated from thirty to forty degrees higher than the best English cast steel.
According to Dr. Pearson’s * analysis, it seems to differ from steel only in containing a little oxide of iron.
He and Mr. Moore obtained the following measures of its specific gravity.



Wootz has been more recently (1819) examined by Mr. Faraday.
The piece which he used was cut from the middle of the cake given by Sir Joseph Banks to Mr. Stodart, when heated cherry-red.
In 460 grains he found besides the carbon and iron, 0.3 of a grain of silex, and 0.6 of a grain of alumine.
The best English cast steel, submitted to the same experiments, yielded no earths.
Mr. Faraday attempted in vain to imitate wootz, although he obtained specimens of iron giving abundance of silex and alumine by analysis.

On a future occasion, however, he was more successful by employing the following method.
Pure steel in small pieces, and in some cases good iron when mixed with charcoal powder were heated intensely for a long time.
In this way were formed carburets highly crystalline, and of a dark metallic grey colour, like the black ore of tellurium.
When broken the facets of several buttons of 500 grains were about the eighth of an inch wide.
This carburet consisted of Iron - - - 94.36 Carbon - - 5.64 * 100.00
This metal when reduced to powder in a mortar was mixed with pure alumine, and the whole subjected to an intense and long heat.
An alumine alloy was thus obtained of a white colour, a close granular texture, and very brittle.
It contained 6.4 of alumine: With 67 parts of this alloy 500 grains of good steel were fused, and formed a perfectly malleable button which forged well, and gave the beautiful damask peculiar to wootz, by the application of dilute sulphuric acid.
This specimen had all the appreciable characters of the best Bombay Wootz.

Hence Messrs. Stodart and Faraday were of opinion that wootz is steel accidentally combined with the metal of the earths, the earth being either in the ore, or derived from the crucible in which the prism is made.
It will appear, say these chemists, from the following experiment, that we had formed artificial wootz when it was not the object of research.
In an attempt to reduce titanium, and combine it with steel, a portion of menachanite was heated with charcoal; a part of the button thus obtained was next fused with some good steel in the proportion of

Steel - - - - 96 Menachanite button - 4. 100

The alloy thus obtained worked well under the hammer, and the bar obtained was evidently superior to steel.
This was ascribed to the presence of titanium, but no titanium could be found in it, not even in the menachanite button itself.
The product was iron and carbon, combined with the earths or their bases, and was in fact excellent wootz.
On this specimen a beautiful damask was produced by the action of dilute acid.

On the Alloys of Steel.

The curious observation of Sir Humphry Davy, that mercury is rendered solid, and experiences a diminution of specific gravity from 13 to 3 by combining with 12'ondth part of ammonium, seems to have impressed on Mr. Stodart's mind the important fact that a very minute quantity of one metal is capable of producing extraordinary effects by combining with another.
Hence he was led, in conjunction with Mr. Faraday, to perform a series of interesting experiments on the alloys of steel with small quantities of gold, silver, platinum, rhodium, iridium, osmium, and palladium.”
A brief account of the results is all that our limits will permit us to give.

1. Alloy of Steel with Silver.
When one part of silver and five hundred of steel were properly fused, a button was produced which forged well, and formed various cutting tools decidedly superior to those made of the very best steel.
The metals were in a state of perfect chemical combination, and by a delicate test the silver could be detected in every part of the alloy.
When more than sindth part of silver was used, the excess was only mixed mechanically with the steel, and a silvery dew exuded from the metal when it contracted by cold or was hammered.

2. Alloy of Steel and Platinum.
An alloy of 100 parts steel and 1 platinum f was forged into bars remarkable for smoothness of surface and beauty of fracture. Though less hard than the preceding alloy, it was considerably tougher.
This alloy is powerfully acted upon by weak sulphuric acid, the action increasing with the quantity of platinum in the alloy. Equal parts of steel and platinum produced a beautiful alloy, which takes a fine polish, and does not tarnish.
It is peculiarly suitable for specula, and its specific gravity is 9.862.

3. Alloy of Steel with Rhodium.
Alloys of steel with from one to two per cent. of rhodium, possess the valuable property of hardness, with tenacity sufficient to prevent cracking either in forging or hardening.
This superior hardness is so remarkable, that in tempering for cutting articles, Messrs. Stodart and Faraday found, that they required it to be heated fully 30° Fahrenheit higher than the best wootz, wootz itself requiring to be heated fully 400 above the best English cast steel.
The great scarcity of rhodium will, however, prevent this alloy from ever getting into general use.

4. Alloy of Steel with Gold.
This alloy is good, though it does not promise to be so valuable as the preceding ones.

5. Triple Alloy of Steel, Iridium, and Osmium.
This alloy is also one of great value.

6. Alloy of Steel with Palladium resembles the preceding.

7. Alloy of Steel with Chromium.
This alloy was first made by M. Berthier, who speaks very favourably of it.
Messrs. Stodart and Faraday fused 16oo grains of steel with 10 of pure chrome.
The button forged well, and though hard showed no disposition to crack.
Another button, made of 1600 grains of steel and 48 of chrome was harder than the first, but was as malleable as pure iron.

Tin and copper were also alloyed with steel, but they did not seem to improve it.

The editor of this work has now before him highly polished specimens of four of these alloys, viz. those of platinum, gold, silver, and rhodium, which were presented to him by the late Mr. Stodart.
They have now been kept for nearly seven years with different specimens of highly polished steel also given him by Mr. Stodart.
The specimens of steel are all rusted, while there is not a spot upon any of the alloys.
The much lamented death of Mr. Stodart has, we fear, delayed for a while the introduction of these valuable alloys into the arts; but we trust the subject will be again resumed by some skilful individual, who unites great practical skill with scientific knowledge.

* Philosophical Transactions, 1822

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@AchimW: is there anything in the text above that you think might be interesting or even useful, or is all the information severely outdated and/or utterly useless ?
And i really value your opinion in this matter.
 
From metallurgical view, the text is between useless and downright false. The interest is in the way the people at that time looked at metallurgy and tried to make better materials by trial and error without fully or even partly understanding the processes involved.
 
Metallurgical Researches of Michael Faraday.

PRIOR to 1819, when Faraday published a paper on the composition of Indian Wootz steel, his contributions to knowledge had been represented by comparatively short communications, with no very obvious connexion.
His first research of any magnitude was, therefore, the one on the alloys of steel with other metals, on which he was engaged for the next five years.
This work, carried out in collaboration with a Mr. James Stodart, a manufacturer of cutlery and surgical instruments, led to the publication of two further papers in 1820 and 1822.
Of these, the former is an account of small scale experiments made in the laboratory of the Royal Institution, and the latter, on ingots, J'() lb.- 20 lb. in weight, melted in Sheffield.
The cause of this interest in steel cannot now with certainty be determined, but Faraday's association with Stodart, and a decision of the Board of Management of the Royal Institution of 1812 that it was desirable that experiments should be undertaken on the alloys of metals, may both have played important parts.
That Stodart's influence was probably considerable is indicated both by the subject of Faraday's first metallurgical contribution and by the fact that after Stodart's death, in 1823, no further paper on this subject appeared.
Faraday's diary contains but three further references to steel, the last of which is dated June 28, 1824.
That Stodart was much impressed by the Wootz steel is shown by his trade card, preserved in the British Museum, which reads: "J. Stodart, at 401, Strand, London, Surgeons Instruments, Razors and other Cutlery made from Wootz, a steel from India, preferred by Mr. Stodart to the best steel in Europe after years of comparative trial ".
The desire to imitate this steel for surgical and other cutlery was clearly one of the main objects of Faraday's research, the other to prepare an alloy suitable for mirrors which would not corrode.

Before discussing the results to which this work led, it is not without interest to attempt to discover why it came to such a sudden and untimely end.
For this, Stodart's death must in some measure be held responsible ; for after giving Faraday every credit for his (in all probability very large) share in the work, the practical experience and keen interest of his collaborator must have exercised a considerable influence.
This, probably, with a growing enthusiasm for other lines of research, and a feeling of disappointment with the results obtained from his work on steel, evidently caused his interest to wane.
The opinions of his scientific contemporaries are well indicated by the following extract from the obituary notice to Faraday in the Proceedings of the Royal Society : "The results of the paper on steel by Stodart and Faraday to the Royal Society in 1822, were of no practical value, and this, one of his first and most laborious investigations, is strikingly distinguished from all his other works by ending in nothing ".
That the research was laborious is well shown by one of Faraday's own letters, in which he says: "Pray, pity us that, after two years' experiments, we have got no further; but I am sure, if you knew the labour of the experiments, you would applaud us for our perseverance at least ".
What, then, were the fruits, if any, of this five years of continued research ?
It is to Faraday's credit that, for the first time, a series of steels were examined with sixteen different metallic additions and of varying concentrations.
Secondly, he determined, in all probability as accurately as has been done even to the present day, the solid solubility, which he gives as 0·2 per cent, of silver in steel.
This was, the writer believes, the first time that such a determination had ever been made.
He further showed that both platinum and rhodium dissolve in steel in all proportions ; for the former metal this was confirmed in 1907, whilst for the latter it still remains the only research ever carried out.
Faraday prepared the first of the 'stainless steels '.
That the alloy contained 50 per cent of platinum, and hence found no useful application, does not detract from a scientific discovery of first-rate importance.
Next, by treatment of a steel with acid, he prepared from it a " soft, grey, plumbaginous powder" which, he says, "appears to be a carburet of iron ".
Priestley, it is believed, had done this at an even earlier date, but Faraday's rediscovery of iron carbide in steel appears to have been entirely independent.
By heating a polished surface of his chromium steel, Faraday developed its structure ; the very first use of the process now known as 'heat-tinting'.
In considering the effect of titanium on steel, he came to the conclusion, which is most generally accepted to-day, that this element does exert a distinctly beneficial effect, but that it finds no permanent place in the steel to which it is added.
Considering his experiments on the rusting of the special steels, he points out that nickel reduces the tendency to corrode, and that, other things being equal, a high carbon steel rusts more rapidly than does one of lower carbon content.
Finally, he observes that his rhodium steel is more resistant to softening by tempering than a plain carbon alloy is, a conclusion which, if followed up, might well have led to the production of steels of the high-speed type long before they were actually devised.
This, then, is part of the fruit of a research which "ended in nothing".
If, however, both Faraday and his scientific contemporaries failed to realise the importance of the results which had been obtained, and to build upon the foundations which he had laid, there are clear indications that a certain section of the producers of steel were greatly impressed.
 
The one steel which Faraday picks out from all he produced was that containing a small percentage of silver.
In his own words, "its alloy with steel is the most valuable of those which we have made.
To enumerate its applications would be to name almost every edge-tool.
It is also probable that it will prove valuable for making dies, especially with the best Indian steel."
In the later paper, dealing 'hith the large scale experiments, he again says that it "was harder than the best cast steel or even than the Indian Wootz, with no disposition whatever to crack either under the hammer or in hardening - its application will probably be extended not only to the manufacture of cutlery, but also to various descriptions of tools; the trifling addition of price cannot operate against its very general introduction.
The silver alloy may be advantageously used for almost every purpose for which good steel is required."
Even today there is on the market the so-called ' silver-steel ', which, in general, is quite free from that metal, the name referring merely to a high class, high-carbon crucible alloy.
The writer well remembers a visit to a crucible steel works in Sheffield some twenty-five years ago, and seeing the head-melter, with much ostentation, dropping a sixpenny piece into the ' pot ' containing some sixty pounds of liquid steel, which addition he was assured would confer on the metal superlative qualities.
There can be very little doubt that both the name and the practice are the direct result of Faraday's work, and provide some indication of the esteem in which it was held by the actual steel-makers.

What has become of the ingots cast in Sheffield will in all probability never be known, but of the steels prepared in the Royal Institution we have now a most interesting and detailed knowledge.
A wooden box labelled ' Faraday' and 'Steel and Alloys ', the former probably, and the latter almost certainly, in his own writing, has recently come to light.
This contained seventy-nine specimens, which were handed over to Sir Robert Hadfield for investigation.
An account by him of an examination of these, which historically is of the very first importance, has now been published (Phil. Trans., A, vol. 230, p. 221, and British Assoc., Sept. 24, 1931).
The scrupulous care taken of this unique material is indicated by the fact that although about 430 separate chemical estimations have been made, with 210 other determinations of structure, hardness, specific gravity, resistance to corrosion, magnetic and electrical characteristics, etc., more than 6½ lb. of the steel still remains, from an original weight of less than 8 lb., representing more than seventy-five per cent of the total.
Broadly, the samples fall into the following categories : In group A are three ' buttons ', evidently the original melts as they solidified from the furnace.
These, like the samples in group B, weigh at most 4-5 oz., the latter section, however, consisting of roughly hammered ' blooms '.
In group C these small ' blooms ' have been further hammered into bars.
One such bar, however, is far more regularly fashioned, and from its analysis Sir Robert Hadfield draws the perfectly logical deduction that it may well have formed a portion of the steel which Faraday used as the raw material for some of his melts.
The other type of basis metal appears to have been an English wrought iron of low carbon and considerable purity for a material of such origin.
That a low carbon base must have been employed for some of the melts is shown by the fact that among the samples which have already been analysed is one which contains only 0·07 per cent of carbon and 2·25 per cent of platinum.

Some idea of the quality of this achievement, bearing in mind the primitive apparatus available, will, perhaps, be better appreciated if it is pointed out that when, some seventy years later in 1894, Arnold carried out his classical research on " The Influence of Elements on Iron " with an equipment vastly more complete and satisfactory than anything which Faraday had at his disposal, in three cases only out of ten was a smaller amount of carbon present in the alloy than in this remarkable material which Faraday turned out in his simple ' blast-furnace '.
The importance of the production of an untarnishable steel for mirrors in this research is shown by a whole group of other samples with one or more highly polished surface.
Among the samples from the Royal Institution, the high platinum-metal alloys were not represented.
The steel noted by Faraday which, as a result of the large proportion of platinum it contained, did not corrode, was not, therefore, examined.
Quite recently, however, a further series of samples, the property of Mr. A. Evelyn Barnard, has been discovered by Sir Henry Lyons.
These also have been placed at Sir Robert Hadfield's disposal for examination, and in a preliminary note in the paper read before Section G (Engineering) of the British Association, high platinum, rhodium, and palladium steels, of such a composition that they can only represent Faraday's alloys, have been found.
To all interested in metallurgy, in Faraday himself, and in the history of scientific discovery, the investigation of these alloys will be a matter of the greatest interest.

Nature, 9 January 1932

F. C. T.
 
If you've read this far you will probably also want to read this long thread with pictures from 2012 on Sharprazorpalace.com:

Calling on the historical experts, I'm stumped! An unassuming mystery razor.

Faraday's associate Stodart was a maker of surgeon's instruments, razors and other cutlery in wootz steel, and apparently also made razors from wootz alloyed with platinum, wootz alloyed with iridium & osmium, and wootz alloyed with rhodium.
 
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