Year: 1898

page_text: A communication from abroad by Dr. LUDWIG MACH, of Villa Brueninghaus,
Kalaische Strasse, Jena, Germany.
I ALFRED GEORGE BROOKES, of 55 and 56, Chancery Lane, in the County of
London, Chartered Patent Agent, do hereby declare the nature of this invention
to be as follows:-
This invention relates to a new and improved alloy of aluminium and mag-
nesium. Heretofore as is known to those familiar with the art a most valuable
quality of aluminium, its small specific gravity (2.64), could not be made use of
to the degree desired, because it was impossible neatly or finely to work the pure
aluminium with cutting tools. The faces worked show tears, the chips are com-
posed of short splinters, the tools do not cut but tear. Files are stopped up after
a few touches and are rendered ineffective so that the hand manipulating the
file has more the feeling of ineffectually rubbing than that of shaping chips. In
this respect the pure aluminium is inferior in these qualities to pure copper
which, as is known, offers great difficulties to being worked.
Hence, for many years, experiments have been directed to the improvement
of the technological qualities of the aluminium by adding heavy metals such as
copper, nickel, etcetera, naturally not without entailing a corresponding increase
of specific weight. Although the chief advantage of the aluminium was thereby
partly sacrificed, the improvement in result obtained did not answer expecta-
tions, it being impossible to turn, to shape, to mill clean or satisfactory faces or
to cut sharp threads on pieces worked from these alloys of aluminium generally
made use of.
Further it was found to be impossible to work them with good effect with fine
files.
This invention relates to an alloy of aluminium, which allows of the working
by cutting tools in a perfect manner and yet diminishes the specific weight of
the pure aluminium.
It has been demonstrated by numerous experiments that magnesium with its
lighter specific gravity (1.74) alloyed with aluminium in certain proportions gives
the latter those qualities with respect to its mechanical working and strength,
which the pure aluminium does not possess.
From these experiments it resulted that, in order to produce the qualities men-
tioned as little as 10 and no less than 30 parts by weight of magnesium may be
added to 100 parts of aluminium, and that the proportion of 10 to 25 parts of
magnesium to 100 parts of aluminium was the most advantageous.
If 100 parts of aluminium are alloyed with 10 parts of magnesium the alloy
has about the same mechanical qualities as rolled zinc. An alloy of 100 parts
of aluminium and 15 parts magnesium corresponds to good foundry-brass while
an alloy of 100 parts of aluminium and of 20 parts of magnesium gives the metal
077

page_text: the character of a softer red brass or a brass wire hard-drawn and finally an alloy
of 25 parts of magnesium and 100 parts of aluminium represents the qualities of
usual red brass.
This alloy may be founded in a thin fusible state. The pieces founded exhibit
long curls of chips in Turning or boring; threads can be cut with sharp profiles
and the bore holes are very fine and neat. The file makes a fine and regular
"touch" or cut without tearing or becoming stopped up. In filing the usual
characteristic noise is heard. Heretofore only coarse or middling files could be
employed, naturally at the cost of exactness; this alloy permits the use even of
the finest files.
The pure aluminium can be cut with a knife like zinc while the new alloy
behaves like a piece of red brass beneath the edge of the knife. Yet these alloys,
especially the softer alloys (100 parts Al and 10 to 15 parts Mg) are very ductile
and can be forged in a cold state, milled to plates, drawn to tubes and wire and
possess therefore the very valuable qualities of the pure aluminium.
The hardness and strength of the new alloy are so eminent that even axes,
cock-pegs, etcetera can be manufactured from it. The polish can be carried to
brilliancy and is of an extraordinary resistance to the influence of the atmosphere.
The colour of the alloy is nearly silver-white differing from that of the pure
aluminium the colour of which is somewhat unsightly. Besides these valuable
workable qualities this new alloy of aluminium and magnesium possesses the
invaluable superiority that the specific weight not only is not increased but is
even reduced.
To this alloy of aluminium and magnesium heavy metals and alloys of them
may be added, such as copper, nickel, tungsten and German silver; but except
when intended for special purposes such an addition is not advisable, because on
the one hand the specific weight of the alloy is increased and on the other hand
one can attain even to the finest modifications all the mechanical qualities by the
aluminium-magnesium-alloy such as hardness and workable qualities.
It has become evident that with such additions the best results are obtained
if only as much of the heavy metal is added to the alloy of aluminium and mag-
nesium so long as the specific gravity of the pure aluminium be not exceeded.
An addition of heavy metals to alloys containing more than 20 parts of mag-
nesium to 100 parts of aluminium would be quite useless because the usual
hardness and initial brittleness characteristic of this addition would be disad-
vantageous to the working of the alloy.
Dated the 25th day of November 1898.
WM. BROOKES & SON,
55 and 56, Chancery Lane, London,
Agents for the Applicant.
A New and Improved Alloy of Aluminium and Magnesium.
A communication from abroad by Dr. LUDWIG MACH, of Villa Brueninghaus,
Kalaische Strasse, Jena, Germany.
I ALFRED GEORGE BROOKES, of 55 and 56, Chancery Lane, in the County of
London, Chartered 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:-
-
This invention relates to a new and improved alloy of aluminium and mag-

page_text: nesium. Heretofore as is known to those familiar with the art a most valuable
quality of aluminium its small specific gravity (2.64), could not be made use of
to the degree desired, because it was impossible neatly or finely to work the pure
aluminium with cutting tools. The faces worked show tears, the chips are com-
posed of short splinters, the tools do not cut but tear. Files are stopped up after
a few touches and are rendered ineffective so that the hand manipulating the
file has more the feeling of ineffectually rubbing than of shaping chips. In
this respect the pure aluminium is inferior in these qualities to pure copper
which, as is known, offers great difficulties to being worked.
Hence for many years, experiments have been directed to the improvement
of the technological qualities of the aluminium by adding heavy metals such as
copper, nickel, etcetera, naturally not without entailing a corresponding increase
of specific weight. Although the chief advantage of the aluminium was thereby
partly sacrificed, the improvement in result obtained did not answer expecta-
tions, it being impossible to turn, to shape, to mill clean or satisfactory faces or
to cut sharp threads on pieces worked from these alloys of aluminium generally
made use of.
Further it was found to be impossible to work them with good effect with fine
files.
This invention relates to an alloy of aluminium, which allows of the working
by cutting tools in a perfect manner and yet diminishes the specific weight of
the pure aluminium.
It has been demonstrated by numerous experiments that magnesium with its
lighter specific gravity (1.74) alloyed with aluminium in certain proportions gives
the latter those qualities with respect to its mechanical working and strength,
which the pure aluminium does not possess.
From these experiments it resulted that, in order to produce the qualities men-
tioned as little as 10 and no less than 30 parts by weight of magnesium may be
added to 100 parts of aluminium, and that the proportion of 10 to 25 parts of
magnesium to 100 parts of aluminium was the most advantageous.
If 100 parts of aluminium are alloyed with 10 parts of magnesium the alloy
has about the same mechanical qualities as rolled zinc. An alloy of 100 parts
of aluminium and 15 parts magnesium corresponds to good foundry-brass while
an alloy of 100 parts of aluminium and of 20 parts of magnesium gives the metal
the character of a softer red brass or a brass-wire hard-drawn and finally an alloy
of 25 parts of magnesium and 100 parts of aluminium represents the qualities of
usual red brass.
66
"
This alloy may be founded in a thin fusible state. The pieces founded exhibit
long curls of chips in turning or boring; threads can be cut with sharp profiles
and the bore holes are very fine and neat. The file makes a fine and regular
'touch or cut without tearing or becoming stopped up. In filing the usual
characteristic noise is heard. Heretofore only coarse or middling files could be
employed, naturally at the cost of exactness; this alloy permits the use even of
the finest files.
The pure aluminium can be cut with a knife like zine while the new alloy
behaves like a piece of red brass beneath the edge of the knife. Yet these alloys
especially the softer alloys (100 parts Al and 10 to 15 parts Mg) are very ductile
and can be forged in a cold state, milled to plates, drawn to tubes and wire and
possess therefore the very valuable qualities of the pure aluminium.
The hardness and strength of the new alloy are so eminent that even axes,
cock-pegs, etcetera can be manufactured from it. The polish can be carried to
brilliancy and is of an extraordinary resistance to the influence of the atmosphere.
The color of the alloy is nearly silver white differing from that of the pure
aluminium the colour of which is somewhat unsightly. Besides these valuable
workable qualities this new alloy of aluminium and magnesium possesses the
invaluable superiority that the specific weight not only is not increased but is
even reduced.

page_text: The alloy of aluminium and magnesium is obtained by melting down potassium-
chloride in a plumbago crucible, then adding the aluminium, and bringing this
metal also to the point of melting.
On the liquid alumnium there lies a transparent layer of liquid potassium
chloride through which is observable the aluminium both possessing the brilliancy
of mercury.
The magnesium is added in small lumps which are quickly dipped into the
fluid aluminium, through the potassium-chloride covering (or coating), and then
stirred until they dissolve. The potassium-chloride coating prevents the com-
bustion of the magnesium and enables the proper percentage of the composition
to be accurately maintained.
To this alloy of aluminium and magnesium, heavy metals and alloys of them
may be added, such as copper, nickel, tungsten and Germen silver; but except
when intended for special purposes such an addition is not advisable, because on
the one hand the specific weight of the alloy is increased and on the other hand
one can attain even to the finest modifications all the mechanical qualities by the
aluminium-magnesium alloy such as hardness and workable qualities.
It has become evident that with such additions the best results are obtained
if only as much of the heavy metal is added to the alloy of aluminium and mag-
nesium so long as the specific gravity of the pure aluminium be not exceeded.
An addition of heavy metals to alloys containing more than 20 parts of mag-
nesium to 100 parts of aluminium would be quite useless because the unusual
hardness and initial brittleness characteristic of this addition would be disad-
vantageous to the working of the alloy.
I am aware that various experiments for alloying aluminium with magnesium
have been made beginning at about the time when aluminium was discovered.
Wöhler (Annalen der Chemie und Pharmacie, 1866, vol. 138, p. 253) fused
these two metals together in the proportions represented by AlMg forming an
alloy with 69.2 per cent. of aluminium. The product was a tin white mass very
brittle igniting at red heat and burning with a white flame similar to magnesium
alone. The alloy in the proportions Mg, Al, containing 36 per cent. of aluminium,
was malleable but completely destroyed by leaving in water for a day, without
any evolution of hydrogen. Wöhler stated his opinion with regard to these
alloys as follows: Both these mixtures appeared to contain a compound of
definite composition, for when treated with a solution of sal-ammoniac they dis-
engaged hydrogen abundantly and deposited a brilliant tin white metallic
powder. The solution contained magnesium chloride, while the residue was rich
in aluminium and appeared to produce some aluminate of magnesium, which
clouded the solution. The metallic residue was washed with water, again treated
with sal-ammoniac solution and then with solution of caustic soda until it no
longer evolved hydrogen. This residue was about one third the total alloy, and
was insoluble in both the above reagents. It burned with brilliant sparks, when
thrown into a flame.
Parkinson (Journal für practische Chemie, vol. 101, p. 375) after his experi-
ments with magnesium-alloys says: None of the magnesium-aluminium alloys
promises any practical utilisation, and this at a time when Wöhler's experiments
had long been known.
Muspratt (Technische Chemie, edition IV. vol. V, p. 1026) comprises the result
of the experiments made by White, Wanklyn and Chapman, Parkinson, Mellor
so that all the alloys are very brittle and are more or less oxidised by the air and
decomposed water to a certain extent.
Even to the present time this view has remained unchanged. This can be seen
by the circumstance that a modern author such as Richards who has thoroughly
treated of aluminium has nothing else to mention of the alloy of aluminium and
magnesium but the results from the experiments of Wöhler enumerating as he
does the same compounds Al,Mg (alloy with 69% Al) and MgAl (alloy with
36% Al) and the same result as Wöhler, and this at a time when the practical

page_text: importance was established beyond all doubt which was not the case at the time
of Wöhler (cf. Richards, Aluminium, edition II, p. 400). Once more magnesium
in connection with aluminium is mentioned in the Specification of Letters Patent
No. 21575 dated 13 November 1895. To obtain an alloy of aluminium possessing
a greater tenacity than pure aluminium has, aluminium is mixed with tungsten
or magnesium as a copper-tin-tungsten-alloy or copper-n-magnesium-alloy.
Magnesium is contained in vanishing quantities (4%) in this alloy of which
4 to 10% are added to the aluminium so as to leave still smaller quantities in
the final alloy.
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:-
―
1. An aluminium-magnesium alloy herein described comprising aluminium
and magnesium in such proportions that a workable metal is obtained.
2. An aluminium-magnesium alloy herein described comprising 100 parts
aluminium and 10-30 parts magnesium, substantially as set forth.
3. An aluminium-magnesium alloy herein described comprising 100 parts
aluminium and 10 to 30 parts magnesium certain predetermined results being
obtainable through the addition of certain quantities of said magnesium within
the said limit aforesaid, substantially as set forth.
4. An alloy comprising 100 parts aluminium 10-30 parts magnesium and a
given quantity of copper, nickel, German silver or other suitable alloying metal,
substantially as, in the manner and for the purposes described.
5. An alloy comprising 100 parts aluminium 10-30 parts magnesium and
copper, nickel, German silver or other suitable alloying metal in such propor-
tions that the specific weight of the composition not exceeds that of aluminium.
Dated the or CHA 03 February EX
Dated the word day (3
WM. BROOKES & SON,
55 and 56, Chancery Lane, London,
Agents for the Applicant.