Improvements in Aluminium Alloys and in the Manufacture thereof.
Year: 1890

page_text: Date of Application, 17th Nov., 1890
Complete Specification Left, 30th Apr., 1891-Accepted. 30th May, 1891
PROVISIONAL SPECIFICATION.
[Communicated from abroad by JOHN W. LANGLEY, of Edgewoodville, Allegheny
County, Pennsylvania, United States of America, Chemist.]
Improvements in Aluminium Alloys and in the Manufacture
thereof.
1 JAMES JOHNSON of 4 Clayton Square Liverpool in the County of Lancaster
Patent Agent do hereby declare the nature of this invention to be as follows :-
My invention which relates to an improvement in alloys of aluminium, is based
upon a discovery which I have made that aluminium when alloyed with titanium,
especially in certain proportions, gives a new product, which together with the
many useful properties of aluminium which reuder it capable of such varied
application in the arts, possesses other beneficial properties in which aluminium is
deficient. Thus I have found that although pure aluminiumn is somewhat soft, and
only slightly elastic, even after hammering or rolling, if it be alloyed with
between one half of one per cent. and ten per cent. of titanium, a product is obtained
intrinsically harder than aluminium, approximately as incorrodible, and capable of
acquiring by hammering or rolling, a degree of elasticity and hardness comparable
to spring brass. Such alloy is fusible at a temperature below the melting point
of steel, and it is with reference to this temperature that I use the word fusible
in the Specification and claims. Its fusing point and specific gravity increase with
the proportion of titanium which it contains. When the proportion of titanium is
less than five per cent., the alloy is nearly as malleable as pure aluminium. There-
fore the alloy when it contains less than ten per cent. of titanium, is of marked value
in the arts, and although I intend to claim it herein specifically, I do not exclude
from the scope of the broad claims, an aluminium alloy containing titanium in
higher per centage, since such alloy may be utilized with advantage as an alloying
material with aluminium to obtain a diluted alloy containing a less per centage of
titanium.
I have found that the presence of iron or silicon in the alloy is deleterious, and
tends to make it brittle and non malleable. Care should therefore be taken in the
manufacture of the alloy that these clements should not be combined in any
considerable proportion.
The obviously undue cost of alloying such rare metals as titanium &c., with
aluminium by simple fusion of the metallic elements has led to attempts to make the
alloy by the reduction of their oxides in the presence of aluminium, but hitherto
such attempts have not risen above the category of mere unsatisfactory laboratory
experiments and have not demonstrated the feasibility of producing such alloy as a
useful article of commerce. I have succeeded in solving the problem thus
presented, and for the first time have made it possible to produce a useful alloy of
the kind above described in a cheap and ready inanner. Chromium, however, when
added to the alloy of aluminium and titanium in small proportion is of substantial
benefit in increasing the elasticity of the product.
I shall now describe a method by which my improved alloy can be made
economically and with facility.
In practising said method I proceed as follows:-I make by fusion a bath of
fluorides of aluminium and sodium or of fluoride of sodium, or of fluorides of
aluminium, sodium, and calcium, or generally a fluoride or fluorides of a metal or
metals more electro-positive than aluminium. I may add to these fluorides-
chlorides of the alkalies or alkaline earths, but these are unnecessary. Cryolite of
commerce may be used as the fluoride constituent of the bath, but although I do
not exclude its use from the scope of the broad claim of this application, it is in
some respects disadvantageous because of its iron, which in the alloying process

page_text: hereinafter described is reduced and by mingling with the alloy, impairs its quality.
For this reason I prefer to employ the above mentioned fluorides in as pure state as
possible. Either before or after the fusion of this fluoride bath 1 add to it a
reducible oxide or salt of the rare metal to be alloyed-in making an alloy of
aluminium and titanium, titanic oxide is preferably used, and after thorough
admixture of these substances I introduce the aluminium. A. reaction between the
aluminium and said oxide or salt at once takes place, the oxide or salt is reduced,
its oxygen or acid radical combines with a part of the aluminium, and the freed
metallic base immediately alloys with the remainder of the aluminium. In practice
I prefer to use as the fluoride-bath, fluorides of aluminium and sodium, which may
be employed in amount ranging from 100 to 400 per cent. of the weight of the
aluminium intended to be added. This bath I melt in a carbon crucible, and
add thereto the oxide or salt of the metal to be alloyed.
When the whole mass is incorporated and as nearly fluid as possible, I charge
metallic aluminium into the crucible, the relative proportions of the aluminium and
oxide or salt being such that the per centage of oxide or salt shall be about twice
the per centage in which its metallic base is desired to be present in the alloy.
Immediately on the introduction of the aluminium, the reaction above noted takes
place between the aluminium and the oxide or salt, and is accompanied by a rapid
elevation of temperature of the bath.
After waiting until further reaction ceases, which is indicated by cessation of rise
of the temperature, the contents of the crucible are poured into a suitable receptacle,
and after cooling somewhat, the melted fluoride can be separated as a supernatant
slag from the metallic alloy at the bottom of the vessel. The alloy is then collected
and is preferably remelted to cleanse it thoroughly from slag and otherwise to
improve its properties.
It is important that the reduction of the oxide or salt of titanium and its alloying
with the aluminium should be conducted in a non-silicious crucible, (preferably a
carbon crucible) since if the vessel be silicious in its composition, a considerable
portion of silicon will be alloyed with the aluminium and titanium, producing a
compound of inferior quality.
When it is desired that the chromium should be present in the alloy, I may vary
the above described process by introducing oxide of chromium with the oxide of
titanium into the fluoride bath so that metallic chromium, as well as titanium shall
be reduced and alloyed with the aluminium or I may first make an alloy of
aluminium and chromium and mix it in a molten state in proper proportion with the
molten alloy of aluminium and titanium.
Dated 1 3 CNT1001
COMPLETE SPECIFICATION.
Improvements in Aluminium Alloys and in the Manufacture
thereof.
I JAMES JOHNSON of 4 Clayton Square Liverpool in the County of Lancaster,
Patent Agent do hereby declare the nature of this invention and in what manner
the same is to be performed, to be particularly described and ascertained in and
by the following statement :-
My invention so far as it relates to an improvement in alloys of aluminium, is
based upon a discovery which I have made that aluminium when alloyed with
titanium especially in certain proportions gives a new product, which together with
the many useful properties of aluminium which render it capable of such varied
application in the arts, possesses other beneficial properties in which aluminium is
deficient. Thus I have found that although pure aluminium is somewhat soft and
only slightly elastic even after hammering or rolling, if it be alloyed with between
one half of one per cent. and ten per cent. of titanium, a product is obtained
intrinsically harder than aluminium, approximately as incorrodible, and capable of

page_text: acquiring by hammering or rolling, a degree of elasticity and hardness comparable
to spring brass. Such alloy is fusible at a temperature below the melting point of
steel, and it is with reference to this temperature that I use the word fusible in the
Specification and claims. Its fusing point and specific gravity increase with the
proportion of titanium which it contains. When the proportion of titanium is less
than five per cent., the alloy is nearly as malleable as pure aluminium. Therefore
the alloy when it contains less than ten per cent. of titanium, is of marked value in
the arts, and although I intend to claim it herein specifically, I do not exclude
from the scope of the broad claims an aluminium alloy containing titanium in higher
per centage, since such alloy may be utilized with advantage as an alloying
material with aluminium to obtain a diluted alloy containing a less per centage of
titanium.
I have found that the presence of iron or silicon in the alloy is deleterious, and
tends to make it brittle and non-malleable. Care should therefore be taken in the
manufacture of the alloy that these elements should not be combined in any
considerable proportion.
The obviously undue cost of alloying such rare metals as titanium &c. with
aluminium by simple fusion of the metallic elements has lead to attempts to make
the alloy by the reduction of their oxides in the presence of aluminium, but hitherto
such attempts have not risen above the category of mere unsatisfactory laboratory
experiments, and have not demonstrated the feasibility of producing such alloy as a
useful article of commerce. I have succeeded in solving the problem thus presented,
and for the first time have made it possible to produce a useful alloy of the kind
above described in a cheap and ready manner. Chromium however when added to
the alloy of aluminium and titanium in small proportion is of substantial benefit in
increasing the elasticity of the product.
I shall now describe a method by which my improved alloy can be made
economically and with facility, and this method I intend to claim. It may be used
not only in alloying aluminium with titanium, but by substituting for the titanic
oxide or salt the oxides or salts of other metals more electro-negative than
aluminium, the metallic bases of such oxides or salts may be alloyed with aluminium
in like manner. Metals which can be alloyed by this method with aluminium, are
bismuth, cadmium, caesium, cerium, chromium, cobalt, copper, gold, iron, lead,
manganese, molybdenum, nickel, osmium, paladium, platinum, silver, tin, titanium,
tungsten, uranium and zinc.
In practising said method I proceed as follows:-I make by fusion a bath of
fluorides of aluminium and sodium or of fluoride of sodium, or of fluorides of
aluminium, sodium, and calcium, or generally a fluoride or fluorides of a metal or
metals more electro positive than aluminium. I may add to these fluorides-chlorides
of the alkalies or alkaline earths, but these are unnecessary. Cryolite of commerce
may be used as the fluoride constituent of the bath, but although I do not exclude
its use from the scope of the broad claim of this application, it is in some respects
disadvantageous because of its iron, which in the alloying process hereinafter
described is reduced, and by mingling with the alloy, impairs its quality. For this
reason I prefer to employ the above mentioned fluorides in as pure state as possible.
Either before or after the fusion of this fluoride bath 1 add to it a reducible oxide
or salt of the rare metal to be alloyed-in making an alloy of aluminium and
titanium, titanic oxide is preferably used-and after thorough admixture of these
substances the oxides or salts being dissolved in the fluoride, I introduce the
aluminium. A reaction between the aluminium and said oxide or salt at once takes
place, the oxide or salt is reduced, its oxygen or acid radical combines with a part
of the aluminium and the freed metallic base immediately alloys with the remainder
of the aluminium. In practice I prefer to use as the fluoride bath, fluorides of
aluminium and sodium which may be employed in amount ranging from one hundred
to four hundred per cent. of the weight of the aluminium intended to be added. This
bath I melt in a carbon crucible, and add thereto the oxide or salt of the metal to
be alloyed. When the whole mass is incorporated and as nearly fluid as possible, I

page_text: charge metallic aluminium into the crucible, the relative proportions of the
aluminium and oxide or salt being such that the per centage of oxide or salt shall
be about twice the per centage in which its metallic base is desired to be present in
the alloy. Immediately on the introduction of the aluminium, the reaction above
noted takes place between the aluminium and the oxide or salt, and is accompanied
by a rapid elevation of temperature of the bath. After waiting until further
reaction ceases, which is indicated by cessation of rise of the temperature, the
contents of the crucible are poured into a suitable receptacle, and after cooling
somewhat, the melted fluoride can be separated as a supernatant slag from the
metallic alloy at the bottom of the vessel. The alloy is then collected and is
preferably remelted to cleanse it thoroughly from slag, and otherwise to improve its
properties.
It is important that the reduction of the oxide or salt of titanium and its alloying
with the aluminium should be conducted in a non-silicious crucible (preferably a
carbon crucible) since, if the vessel be silicious in its composition, a considerable
portion of silicon will be alloyed with the aluminium and titanium, producing a
compound of inferior quality.
When it is desired that chromium should be present in the alloy, I may vary the
above described process by introducing oxide of chromium with the oxide of
titanium into the fluoride bath so that metallic chromium, as well as titanium shall
be reduced and alloyed with the aluminium, or I may first make an alloy of
aluminium and chromium and mix it in a molten state in proper proportion with the
molten alloy of aluminium and titanium.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed I declare that what I
claim is :-
First. As a new article of manufacture, a metallic alloy of titanium and aluminium,
substantially as described.
Second. As a new article of manufacture, a fusible alloy of titanium and aluminium
containing less than ten per cent. of titanium substantially as described.
Third. As a new article of manufacture, a fusible and malleable alloy of titanium
and aluminium, substantially as described.
Fourth. As a new article of manufacture, a fusible alloy of aluminium titanium
and chromium; substantially as described.
Fifth. In the art of alloying aluminium with metals whose oxides or salts are
difficult of reduction, the method hereinbefore described, which consists in treating
such oxide or salt with molten aluminium in a molten fluoride bath, whereby
the metallic base of the oxide or salt is reduced and alloyed; substantially as
described.
Sixth. In the art of alloying aluminium with metals whose oxides or salts are
difficult of reduction, the method herein before described, which consists in incor-
porating such oxide or salt with a fluoride-bath and then adding aluminium thereto,
substantially as described.
Seventh. In the art of alloying aluminium with metals whose oxides or salts are
difficult of reduction, the method hereinbefore described, which consists in treating
such oxide or salt with molten aluminium in a molten fluoride bath contained in a
non-silicious vessel, whereby the metallic base of the oxide or salt is reduced and
alloyed substantially as described.
Eighth. In the art of alloying aluminium with metals whose oxides or salts are
difficult of reduction, the method hereinbefore described which consists in incor-
porating such oxide or salt in a molten fluoride bath substantially free from iron
and reducing it in such bath with molten aluminium; substantially as described.
11
ليوم
די
1001