THE MANUFACTURE OF USEFUL ALLOYS OF ALUMINIUM
Year: 1858

page_text: LETTERS PATENT to Edmund Leopold Benzon, of Sheffield, in the County
of York, Steel Manufacturer, for the Invention of "THE MANUFACTURE
OF USEFUL ALLOYS OF ALUMINIUM."-A communication.
Sealed the 25th January 1859, and dated the 1st December 1858.
PROVISIONAL SPECIFICATION left by the said Edmund Leopold Benzon
at the Office of the Commissioners of Patents, with his Petition, on the
1st December 1858.
I, EDMUND LEOPOLD BENZON, of Sheffield, in the County of York, Steel
Manufacturer, do hereby declare the nature of the said Invention for "THE
MANUFACTURE OF USEFUL ALLOYS OF ALUMINIUM," to be as follows:-
The Invention consists in the decomposition of aluminium by carbon in the
presence of and in contact with electro-positive metals (as, for instance, copper,
iron, &c.,) or their oxides, and in the simultaneous production (that is to say,
in the same melting,) of the corresponding alloys of aluminium, and the above
mentioned metals or their oxides.
In order more fully to elucidate the nature of the Invention, I will describe
the production by its means of the alloy of aluminium and copper.
I take protoxide of copper, or peroxide of copper, or also granulated copper,
and mix this with alumina obtained from alum or other salts of alumina, and

page_text: with carbon (either animal or vegetable), according to proportions of weight
or measure to be more fully stated and defined in my Specification.
The alumina and carbon must be reduced to a fine powder, and most
thoroughly mixed with the copper, so as to have the copper, alumina, and
carbon as thoroughly intermixed as can be done mechanically. This mixture
I compress, if necessary, by mechanical means, or place it loose in a crucible,
similar to those employed in the melting of steel, and I melt the mass with
gradually increasing heat. When the mass is well melted, the alloy 1 intend
to produce (which in this instance is that of aluminium and copper,) will be
found in the bottom of the crucible, and can be poured without allowing the
slag to mix with it into any mould, thereby producing an ingot, which can
afterwards, by hammering, rolling, pressing, or other mechanical means, be
reduced into any desired shape. The alloy produced is capable of receiving a
very high polish, has in colour a close resemblance to gold, and has the
property of comporting itself when exposed to the atmosphere like, and is about
as stable as, the precious metals. This alloy can in many instances be
applied in. the arts for the same purposes as copper, bronze, silver, gold, or
other metals or metallic alloys. In a similar manner I produce the alloy of
aluminium and iron, which can be used with great advantage in the manu-
facture of cast steel, and of all other descriptions of steel wherein
great sound-
ness and beautiful bright silvery finish are desirable. When I employ the
alloy of aluminium and iron in the manufacture of cast steel, I may either
introduce into the crucible protoxide, peroxide, or magnetic oxide of iron,
thoroughly intermixed as described, with aluminium and carbon in a powdered
state, and melt them down together with the steel; or I may produce the alloy
of iron and aluminium by itself, and add it in proportions to be stated in my
Specification to the steel while in the progress of melting.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Edinund Leopold Benzon in the Great Seal Patent Office
on the 1st June 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDMUND
LEOPOLD BENZON, of Sheffield, in the County of York, Steel Manufacturer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the First day. of. December, in the year of our Lord

page_text: One thousand eight hundred and fifty-eight, in the twenty-second year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Edmund Leopold Benzon, Her special license that I, the said Edmund
Leopold Benzon, my executors, administrators, and assigns, or such others
as I, the said Edmund Leopold Benzon, my executors, administrators, and
assigns, should at any time agree with, and no others, from time to time and
at all times thereafter during the term therein expressed, should and lawfully
might make, use, exercise, and vend, within the United Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an Invention for
THE MANUFACTURE OF USEFUL ALLOYS OF ALUMINIUM," being a communication
from abroad, upon the condition (amongst others) that I, the said Edmund
Leopold Benzon, by an instrument in writing under my hand and seal, should
particularly describe and ascertain the nature of the said Invention, and in
what manner the same was to be performed, and cause the same to be filed
in the Great Seal Patent Office within six calendar months next and imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Edmund Leopold Benzon, do hereby
declare the nature of the said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement (that is to say):-
This Invention has for its object the manufacture of useful alloys of
aluminium by the decomposition of alumina or the oxide of aluminium, by
means of carbon, in the presence of and in intimate contact with certain metals
electro-positive to aluminium (such, for instance, as copper or iron, or their
oxides), so as to cause the aluminium to combine in any desired proportion
with the electro-positive metal, and form an alloy. The alloy or alloys is or
are produced by the close and intimate contact of the carbon, alumina, and the
electro-positive metal or their oxides in each other's presence, and their simul-
taneous decomposition or reduction by the application of suitable heat.
In order, however, more fully to explain the nature of the Invention, I will
first describe the manner of producing by means of the improved process an
alloy of aluminium and copper.
I take protoxide of copper or peroxide of copper or metallic copper in a
granulated or as finely divided state as it can conveniently be obtained, and I
mix this electro-positive metal with alumina (obtained from alum or other
salts of alumina, or from some other convenient source.) The alumina must
also be in a finely powdered state, and I add thereto carbon, giving preference
to animal charcoal finely pulverised. All these three ingredients are to be as

page_text: intimately mixed or blended together as can be done mechanically, and the
ingredients must be combined according to chemical equivalents or atomic
proportions.
1 find in practice that it is desirable to use a little more carbon than is
atomically required for reducing the alumina, as if oxides of copper are used,
a little more carbon must be added than is required for reducing both oxides
(namely, the oxide of copper and the oxide of aluminium (Al, O³). The
mixture is then put into a melting pot or crucible, such as those used in
melting cast steel, and the bottom and walls of the pot should be lined or
covered with carbon, in order to prevent as far as possible any impurities in
the material of which the crucible or pot is composed from affecting the alloy;
and after having covered the mixture with carbon it must be exposed to a
high red heat, say, somewhere about the melting heat of copper, until the
decomposition of the alumina has taken place, and the alumina has been
reduced to the metallic state. The heat may then be increased for about half
an hour or an hour, in order to melt down the mixture of the metals to an
uniform alloy. By this means I am enabled to produce a series of alloys, the
hardness, ductility, and colour of which will depend upon the per-centage of
aluminium contained in them. The proportion of copper or the oxides of
copper to the alumina is immaterial (provided the materials be combined
according to chemical equivalents), as copper and carbon under the above-
named circumstances will always reduce an equivalent proportion of alumina
to the metallic state. If, however, it be desired to produce alloys containing
certain definite per-centages of the metals, I mix copper or any or both of its
oxides with alumina in the proportion required, of course basing the calcu-
lation on the chemical equivalent of the several ingredients, adding an excess
of carbon to ensure the decomposition or reduction of the oxides of the metals.
In order to guard against errors arising from imperfectly conducting the
process s of decomposing the alumina, I sometimes, in order to produce alloys
containing definite per-centages of the metals, find it convenient in the first
place to decompose with the electro-positive metal as large a per-centage of
alumina as can conveniently be done. The alloy thereby produced is then to
be assayed or analyzed in order to ascertain the exact proportion of aluminium
contained therein; after which the required quantity of copper or electro-
positive metal can be readily added, in order to reduce the alloy to exactly the
desired proportion of the two metals. The same process as that adopted with
copper and its oxides can also be employed to reduce alumina with iron and
its oxides. The process is carried on under the same conditions as those

page_text: a
above set forth, with the difference only that a larger excess of carbon must
be used, and a higher heat employed and kept up for a longer period than
when an alloy of copper is to be produced. The reduction of alumina in con-
tact with the oxides of iron (hammer slag, for instance,) is easier than with
pure or metallic iron.
Either of the above alloys of copper or iron may be mixed with other alloys
or metals; for instance, the copper alloy (Cu, Al,) may be mixed with brass
or German silver; zinc or spelter may also be melted down with the copper
alloy (Cu, Al,) and another alloy thereby produced. Alumina may also be
reduced with copper in the presence of zinc or spelter, and a bronze alloy
thereby produced. The iron alloy (Fe, Al), produced in the manner above
described, may be mixed with steel in the melting pot, or the alumina may be
reduced in the melting pot with the steel by adding a suitable quantity of
alumina with an equivalent quantity of carbon, the added ingredients being in
à pulverised or finely divided state, and intimately mixed together.
By causing aluminium to combine with other metals in the manner above
described, the aluminium is obtained in the metallic state, and some of the alloys
so produced, such as the alloy of iron and aluminium, may be subsequently
decomposed, and the pure metallic aluminium obtained separate from the
other metal, and used for any of the purposes for which aluminium is now or
may hereafter be employed. The alloy of copper with aluminium when
perfectly melted, as above described, can be cast into any mould or form, and
can also subsequently be reduced into any desired shape by hammering, rolling,
pressing, or other mechanical operations. This alloy is capable of receiving a
very high polish, and in colour closely resembles gold, and has the property of
comporting itself when exposed to the atmosphere in about the same manner
as gold.
The alloys of aluminium with zinc and copper will produce a bronze of
beautiful colour and greater. hardness than any of the bronzes made in the
ordinary manner.
The alloy of aluminium and iron will be found useful for many mechanical
purposes, especially in the manufacture of cast steel, to which it will impartall
the advantages resulting from increased soundness, hardness, and bright silvery
variegated polish.
Having now described the Invention of the manufacture of useful alloys
of aluminium, as communicated to me by my foreign correspondent, and
having explained the manner of carrying the same into effect, I claim as the
Invention secured to me by Letters Patent as aforesaid, the manufacture of

page_text: useful alloys of aluminium by the decomposition of alumina in the presence of
and in contact with carbon, and an electro-positive metal by the application
of heat to the triple compound.
In witness whereof, I, the said Edmund Leopold Benzon, have hereunto
set my hand and seal, this Thirty-first day of May, One thousand
eight hundred and fifty-nine.
Witness,
W. E. NEWTON,
EDMUND L BENZON. (L.S.)