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fact, that the same quantity of the nickel alloyed with steel,
instead of preventing its rusting, appeared to accelerate it very
rapidly.

Platinum and rhodium have, in the course of these experi-
ments, been alloyed with iron, but these compounds do not
appear to possess any very interesting properties. With gold
we have not made the experiment. The alloys of other metals
with iron, as far as our experience goes, do not promise much
usefulness. The results are very different when steel is used ;
it is only, however, of a few of its compounds that we are pre-
pared to give any account.

Together with some others of the metals, the following have
been alloyed with both English and Indian steel, and in various



64 On the Alloijs of Steel. [ 1 820.

proportions : platinum, rhodium, gold, silver, nickel, copper
and tin.

All the above-named metals appear to have an affinity for
steel sufficiently strong to make them combine : alloys of
platinum, rhodium, gold and nickel may be obtained when
the heat is sufficiently high. This is so remarkable with
platinum, that it will fuse when in contact with steel, at a heat
at which the steel itself is not affected.

With respect to the alloy of silver, there are some very
curious circumstances attending it. If steel and silver be kept
in fusion together for a length of time, an alloy is obtained,
which appears to be very perfect while the metals are in the
fluid state, but on solidifying and cooling, globules of pure sil-
ver are expressed from the mass, and appear on the surface of
the button. If an alloy of this kind be forged into a bar, and
then dissected by the action of dilute sulphuric acid, the silver
appears, not in combination with the steel, but in threads
throughout the mass ; so that the whole has the appearance
of a bundle of fibres of silver and steel, as if they had been
united by welding. The appearance of these silver fibres is
very beautiful ; they are sometimes ^th of an inch in length, and
suggest the idea of giving mechanical toughness to steel, where
a very perfect edge may not be required.

At other times, when silver and steel have been very long in
a state of perfect fusion, the sides of the crucible, and fre-
quently the top also, are covered with a fine and beautiful dew
of minute globules of silver ; this effect can be produced at
pleasure. At first we were not successful in detecting silver
by chemical tests in these buttons ; and finding the steel uni-
formly improved, were disposed to attribute its excellence to
an effect of the silver, or to a quantity too small to be tested.
By subsequent experiments we were, however, able to detect
the silver, even to less than 1 in 500.

In making the silver alloys, the proportion first tried was
1 silver to 160 steel; the resulting buttons were uniformly steel
and silver in fibres, the silver being likewise given out in glo-
bules during solidifying, and adhering to the surface of the fused
button ; some of these when forged gave out more globules of
silver. In this state of mechanical mixture, the little bars, when
exposed to a moist atmosphere, evidently produced voltaic



1820.] On the Alloys of Steel. 65

action, and to this we are disposed to attribute the rapid de-
struction of the metal by oxidation, no such destructive action
taking place when the two metals are chemically combined.
These results indicated the necessity of diminishing the quan-
tity of silver, and 1 silver to 200 steel was tried. Here, again,
were fibres and globules in abundance ; with 1 to 300, the fibres
diminished, but still were present; they were detected even when
the proportion of 1 to 400 was used. The successful experi-
ment remains to be named. When 1 of silver to 500 steel
were properly fused, a very perfect button was produced ; no
silver appeared on its surface ; when forged and dissected by
an acid, no fibres were seen, although examined by a high
magnifying power. The specimen forged remarkably well,
although very hard ; it had in every respect the most favour-
able appearance. By a delicate test every part of the bar gave
silver. This alloy is decidedly superior to the very best steel,
and this excellence is unquestionably owing to combination with
a minute portion of silver. It has been repeatedly made, and
always with equal success. Various cutting tools have been
made from it of the best quality. This alloy is perhaps only
inferior to that of steel with rhodium, and it may be procured
at a small expense ; the value of silver, where the proportion is
so small, is not worth naming ; it will probably be applied to
many important purposes in the arts. An attempt was made
to procure the alloy of steel with silver by cementation : a small
piece of steel wrapped in silver-leaf, being 1 to 160, was put
into a crucible, which being filled up with pounded green glass,
was submitted to a heat sufficient to fuse the silver ; it was
kept at a white heat for three hours. On examining it, the silver
was found fused, and adhering to the steel; no part had com-
bined. The steel had suffered by being kept so long at a high
temperature. Although this experiment failed in effecting the
alloy of steel with silver, there is reason to believe that with
some other metals alloys may be obtained by this process ; the
following circumstance favours this suggestion. Wires of pla-
tinum and steel, of about equal diameter, were packed together,
and, by an expert workman, were perfectly united by welding.
This was effected with the same facility as could have been
done with steel and iron. On being forged, the surface po-
lished, and the steel slightly acted on by an acid, a very novel



66 On the Alloys of Steel. [1820.

and beautiful surface appeared, the steel and platinum forming
dark and white clouds : if this can he effected with very fine
wires, a damasked surface will be obtained of exquisite beauty.
This experiment, made to ascertain the welding property of
platinum, is only named here in consequence of observing that
some of the largest of the steel clouds had much the appear-
ance of being alloyed with a portion of the platinum. A more
correct survey of the surface, by a high magnifying power, went
far to confirm this curious fact : some more direct experiments
are proposed to be made on this apparent alloy by cementation.
The alloys of steel with platinum, when both are in a state
of fusion, are very perfect, in every proportion that has been
tried. Equal parts by weight form a beautiful alloy, which
takes a fine polish, and does not tarnish ; the colour is the
finest imaginable for a mirror. The specific gravity of this
beautiful compound is 9*862.

90 of platinum with 20 of steel gave also a perfect alloy,
which has no disposition to tarnish ; the specific gravity 15*88 :
both these buttons are malleable, but have not yet been applied
to any specific purpose.

10 of platinum to 80 of steel formed an excellent alloy. This
was ground and very highly polished, to be tried as a mirror ;
a fine damask, however, renders it quite unfit for that purpose.
The proportions of platinum that appear to improve steel
for edge instruments, are from 1 to 3 per cent. Experience
does not yet enable us to state the exact proportion that forms
the best possible alloy of these metals ; 1*5 per cent, will pro-
bably be very nearly right. At the time of combining 10 of
platinum with 80 steel, with a view to a mirror, the same pro-
portions were tried with nickel and steel; this too had the
damask, and consequently was unfit for its intention. It is
curious to observe the difference between these two alloys, as
to susceptibility for oxygen. The platinum and steel, after
laying many months, had not a spot on its surface, while that
with nickel was covered with rust ; they were in every respect
left under similar circumstances. This is given as an instance,
showing that nickel with steel is much more subject to oxida-
tion than when combined with iron.

The alloys of steel with rhodium are likely to prove highly
valuable. The scarcity of that metal must, however, operate



1820.] On the Alloys of Steel. 67

against its introduction to any great extent. It is to Dr. Wol-
laston we are indebted, not only for suggesting the trial of
rhodium, but also for a liberal supply of the metal, as well as
much valuable information relative to fuel, crucibles, &c. ; this
liberality enables us to continue our experiments on this alloy ;
these, with whatever else may be worth communicating, will be
given in a future Number of this Journal. The proportions we
have used are from 1 to 2 per cent. The valuable properties
of the rhodium alloys are hardness, with sufficient tenacity to
prevent cracking either in forging or in hardening. This su-
perior hardness is so remarkable, that in tempering a few cut-
ting articles made from the alloy, they required to be heated
full 30 F. higher than the best wootz, wootz itself requiring to
be heated full 40 above the best English cast steel. Thenno-
metrical degrees are named, that being the only accurate
method of tempering steel.

Gold forms a good alloy with steel. Experience does not
yet enable us to speak of its properties. It certainly does not
promise to be of the same value as the alloys of silver, platinum,
and rhodium.

Steel with 2 per cent, of copper forms an alloy. Steel also
alloys with tin. Of the value of these we have doubts. If, on
further trial, they, together with other combinations, requiring
more time than we have been able to bestow on them, should
prove at all likely to be interesting and useful, the results will
be frankly communicated.

Our experiments have hitherto been confined to small quanti-
ties of the metals, seldom exceeding 2000 grains in weight, and
we are aware that the operations of the laboratory are not
always successful when practised on a large scale. There does
not, however, appear to be any good reason why equal success
may not attend the working on larger masses of the metals,
provided the same diligence and means are employed.

From the facility of obtaining silver, it is probable that its
alloy with steel is the most valuable of those 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 when combined with the best Indian
steel. Trial will soon be made with the silver in the large way,
and the result, whatever it may be, will be candidly stated.



08 On the Alloys of Steel. [ 1 822.

Table of Specific Gravities of Alloys, $c. mentioned in the
preceding Paper.

Iron, unhammered 7*847

Wootz, unhammered (Bombay) 7*665

Wootz, tilted (Bombay) . . . V . . .' . 7-6707

Wootz, in cake (Bengal) . . . . - * . . . 7*730

Wootz, fused and hammered (Bengal) . . . 7*787

Meteoric iron, hammered . . . 7'965

Iron, and 3 per cent, nickel 7*804'

Iron, and 10 per cent, nickel 7*849

Steel, and 10 per cent, platinum (mirror) . . 8*100

Steel, and 10 per cent, nickel (mirror) . . . 7*684

Steel, and 1 per cent, gold, hammered . . . 7*870

Steel, and 2 per cent, silver, hammered . . . 7*808

Steel, and 1*5 per cent, platinum, hammered . 7*732

Steel, and 1*5 per cent, rhodium, hammered . 7*795

Steel, and 3 per cent, nickel, hammered . . . 7*750

Platinum 50, and steel 50, unhammered* . . 9*862

Platinum 90, and steel 20, unhammered f . . 15*880

Platinum, hammered and rolled 21*250



On the Alloys of Steel. By STODART and FARADAY J.
[Read March 21, 1822.]

THE alloys of steel made on a small scale in the laboratory of
the Royal Institution proving to be good, and the experiments
having excited a very considerable degree of interest both at
home and abroad, gave encouragement to attempt the work
on a more extended scale; and we have now the pleasure of
stating, that alloys similar to those made in the Royal Insti-
tution have been made for the purpose of manufacture ; and
that they prove to be, in point of excellence, in every respect
equal, if not superior to the smaller productions of the labo-
ratory. Previous, however, to extending the work, the former
experiments were carefully repeated, and to the results were
added some new combinations, namely, steel with palladium,

* The calculated mean specific gravity of this alloy is 11 '2723, assuming the
specific gravity of platinum and steel as expressed in this Table,
f The calculated mean specific gravity of this alloy is 16'0766.
J Philosophical Transactions, 1822, p. 253; also Phil. Mag. vol. Ix. p. 363.



1822.] On the Alloys of Steel. 69

steel with indium and osmium, and latterly, steel with chro-
mium. In this last series of experiments we were particularly
fortunate, having hy practice acquired considerable address in
the management of the furnaces, and succeeded in procuring
the best fuel for the purpose. Notwithstanding the many ad-
vantages met with in the laboratory of the Royal Institution,
the experiments were frequently rendered tedious from causes
often unexpected, and sometimes difficult to overcome ; among
these, the failure of crucibles was perhaps the most perplexing.
We have never yet found a crucible capable of bearing the
high degree of temperature required to produce the perfect
reduction of titanium ; indeed we are rather disposed to ques-
tion whether this metal has ever been so reduced : our furnaces
are equal* (if any are) to produce this effect, but hitherto we
have failed in procuring a crucible.

The metals that form the most valuable alloys with steel are
silver, platinum, rhodium, iridium and osmium, and palladium ;
all of these have now been made in the large way, except in-
deed the last-named. Palladium has, for very obvious reasons,
been used but sparingly ; four pounds of steel with y^th part
of palladium has, however, been fused at once, and the com-
pound is truly valuable, more especially for making instru-
ments that require perfect smoothness of edge.

We are happy to acknowledge the obligations due from us
to Dr. Wollaston, whose assistance we experienced in every
stage of our progress, and by whom we were furnished with
all the scarce and valuable metals ; and that with a liberality
which enabled us to transfer our operations from the labora-
tory of the chemist to the furnace of the maker of cast steel.

In making the alloys on a large scale, we were under the
necessity of removing our operations from London to a steel
furnace at Sheffield ; and being prevented by other avocations
from giving personal attendance, the superintendence of the
work was consequently entrusted to an intelligent and con-
fidential agent. To him the steel, together with the alloying
metals in the exact proportion, and in the most favourable
state for the purpose, was forwarded, with instructions to see
the whole of the metals, and nothing else, packed into the cru-

* We have succeeded in fusing in these furnaces rhodium, and also, though
imperfectly, platinum in crucibles.



70 On the Alloys of Steel. [ 1 822.

cible, and placed in the furnace, to attend to it while there,
and to suffer it to remain for some considerable time in a state
of thin fusion, previous to its being poured out into the mould.
The cast ingot was next, under the same superintendence,
taken to the tilting mill, where it was forged into bars of a
convenient size, at a temperature not higher than just to render
the metal sufficiently malleable under the tilt hammer. When
returned to us, it was subjected to examination both mechanical
and chemical, as well as compared with the similar products of
the laboratory. From the external appearance, as well as from
the texture of the part when broken by the blow of the hammer,
we were able to form a tolerably correct judgement as to its
general merits ; the hardness, toughness, and other properties
were further proved by severe trials, after being fashioned into
some instrument or tool, and properly hardened and tempered.

It would prove tedious to enter into a detail of experiments
made in the Royal Institution ; a brief notice of them will at
present be sufficient. After making imitations of various spe-
cimens of meteoric iron, by fusing together pure iron and
nickel, in proportions of 3 to 10 per cent., we attempted
making an alloy of steel with silver, but failed, owing to a
superabundance of the latter metal ; it was found, after very
many trials, that only the J^Q^ P art f silver would combine
with steel, and when more was used a part of the silver was
found in the form of metallic dew, lining the top and sides of
the crucible : the fused button itself was a mere mechanical
mixture of the two metals, globules of silver being pressed out
of the mass by contraction in cooling, and more of these glo-
bules being forced out by the hammer in forging ; and further,
when the forged piece was examined, by dissecting it with
diluted sulphuric acid, threads or fibres of silver were seen
mixed with the steel, having something of the appearance of
steel and platinum when united by welding : but when the pro-
portion of silver was only j.Jo^ part, neither dew, globules,
nor fibres appeared, the metals being in a state of perfect
chemical combination, and the silver could only be detected
by a delicate chemical test.

With platinum and rhodium, steel combines in every propor-
tion ; and this appears also to be the case with indium and
osmium: from 1 to 80 per cent, of platinum was perfectly



1822.J On the Alloys of Steel 71

combined with steel, in buttons of from 500 to 2000 grains.
With rhodium, from 1 to 50 per cent, was successfully used.
Equal parts by weight of steel and rhodium gave a button,
which, when polished, exhibited a surface of the most exquisite
beauty: the colour of this specimen is the finest imaginable for
a metallic mirror, nor does it tarnish by long exposure to the
atmosphere : the specific gravity of this beautiful compound is
9' 176. The same proportion of steel and platinum gave a good
button, but a surface highly crystalline renders it altogether
unfit for a mirror. In the laboratory we ascertained that, with
the exception of silver, the best proportion of the alloying
metal, when the object in view was the improvement of edge-
tools, was about y^th part, and in this proportion they have
been used in the large way. It may be right to notice, that in
fusing the metals in the laboratory no flux whatever was used,
nor did the use of any ever appear to be required.

Silver being comparatively of little value with some of the
alloying metals, we were disposed to make trial with it as
the first experiment in the large way. 8 Ibs. of very good
Indian steel was sent to our agent, and with it 3^o tn P art f
pure silver : a part of this was lost, owing to a defect in the
mould ; a sufficient quantity was, however, saved to satisfy us
as to the success of the experiment. This, when returned,
had the most favourable appearance both as to surface and
fracture ; 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. Some articles, for various
uses, have been made from this alloy ; they prove to be of a
very superior quality ; its application will probably be ex-
tended 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 pur-
pose for which good steel is required.

Our next experiment made in the large way was with steel
and platinum. 10 Ibs. of the same steel, with T ^o tn P art f pla-
tinum, the latter in the state produced by heating the ammonia
muriate in a crucible to redness, was forwarded to our agent,
with instructions to treat this in the same way as the last-
named metals. The whole of this was returned in bars re-



72 On the Alloys of Steel. [1822.

markable for smoothness of surface and beauty of fracture*
Our own observation, as well as that of the workmen employed
to make from it various articles of cutlery, was, that this alloy,
though not so hard as the former, had considerably more
toughness : this property will render it valuable for every pur-
pose where tenacity, as well as hardness, is required ; neither
will the expense of platinum exclude it from a pretty general
application in the arts ; its excellence will much more than
repay the extra cost.

The alloys of steel with rhodium have also been made in
the large way, and are perhaps the most valuable of all ; but
these, however desirable, can never, owing to the scarcity of
the metal, be brought into very general use. The compound
of steel, iridium, and osmium, made in the large way, is also
of great value ; but the same cause, namely the scarcity and
difficulty of procuring the metals, will operate against its very
general introduction. A sufficient quantity of these metals
may, perhaps, be obtained to combine with steel for the pur-
pose of making some delicate instruments, and also as an article
of luxury, when manufactured into razors. In the meantime,
we have been enabled, repeatedly, to make all these alloys
(that with palladium excepted) in masses of from 8 to 20 Ibs.
each ; with such liberality were we furnished with the metals
from the source already named.

A point of great importance in experiments of this kind
was, to ascertain whether the products obtained were exactly
such as we wished to produce. For this purpose, a part of
each product was analysed, and in some cases the quantity
ascertained ; but it was not considered necessary in every case
to verify the quantity by analysis, because, in all the experi-
ments made in the laboratory, the button produced after fusion
was weighed, and if it fell short of the weight of both metals
put into the crucible, it was rejected as imperfect, and put
aside. When the button gave the weight, and on analysis
gave proofs of containing the metal put in to form the alloy,
and also, on being forged into a bar and acted on by acids,
presented a uniform surface, we considered the evidence of
its composition as sufficiently satisfactory. The processes of
analysis, though simple, we shall briefly state : the information
may be desirable to others who may be engaged on similar



1822.1 On the Alloys of Steel. 73

experiments ; and further, may enable every one to detect any
attempt at imposition. It would be very desirable at present
to possess a test as simple, by which we could distinguish the
wootz, or steel of India, from that of Europe ; but this, unfor-
tunately, requires a much more difficult process of analysis.

To ascertain if platinum is in combination with steel, a small
portion of the metal, or some filings taken from the bar, is to
be put into dilute sulphuric acid ; there will be rapid action 5
the iron will be dissolved, and a black sediment left, which
will contain carbon, hydrogen, iron, and platinum ; the carbon
and hydrogen are to be burnt off, the small portion of iron
separated by muriatic acid, and the residuum dissolved in a
drop or two of nitromuriatic acid, If a piece of glass be
moistened with this solution, and then heated by a spirit-lamp
and the blowpipe, the platinum is reduced, and forms a metallic
coating on the glass. ^

In analysing the alloy of steel and silver, it is to be acted
on by dilute sulphuric acid, and the powder boiled in the acid ;
the silver will remain in such a minute state of division that
it will require some time to deposit. The powder is then to
be boiled in a small portion of strong muriatic acid * ; this will
dissolve the iron and silver, and the latter will fall down as a
chloride of silver on dilution with water ; or the powder may
be dissolved in pure nitric acid, and tested by muriatic acid
and ammonia.

The alloy of steel and palladium, acted on by dilute sulphuric
acid, and boiled in that acid, left a powder, which, when the
charcoal was burnt from it, and the iron partly separated by
cold muriatic acid, gave on solution in hot muriatic acid, or in
nitromuriatic acid, a muriate of palladium ; the solution, when
precipitated by prussiate of mercury, gave prussiate of palla-
dium ; and a glass plate moistened with it and heated to red-
ness, became coated with metallic palladium.

The residuum of the rhodium alloy obtained by boiling in
diluted sulphuric acid, had the combustible matter burnt off,
and the powder digested in hot muriatic acid : this removed the
iron ; and by long digestion in nitromuriatic acid, a muriate

* Although it is a generally received opinion that muriatic acid does not



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