IMPROVEMENTS IN THE MANUFACTURE OF BRONZE
Year: 1881

page_text: LETTERS PATENT to Henry Hussey Vivian, of Park Wern, Swansea, in the
County of Glamorgan, M.P., for an Invention of "IMPROVEMENTS IN THE
MANUFACTURE OF BRONZE."
PROVISIONAL SPECIFICATION left by the said Henry Hussey Vivian at the
Office of the Commissioners of Patents on the 28th July 1881.
HENRY HUSSEY VIVIAN, of Park Wern, Swansea, in the County of Glamorgan,
M.P. "IMPROVEMENTS IN THE MANUFACTURE OF BRONZE."
This Invention has for its object improvements in the manufacture of bronze.
Generally speaking, the admixture of even a small proportion of antimony with
copper is very injurious to the qualities of the latter metal, and consequently every
care is taken by the copper smelter to get rid of this impurity; but I have found
that when copper is alloyed with tin to form a bronze, the influence of antimony
in due proportion is no longer injurious.
On the contrary, I find that by an addition of antimony I am able to increase
the strength, durability, hardness, and tenacity of alloys of tin and copper called
bronze, so as to impart to the alloy the characteristics desired according to the use
for which it is destined.
I have discovered that the addition of from one fourth to one fifth per cent. of
antimony adds materially to the strength of bronze consisting of from 93 to 96 per
cent. of copper, and 7 to 4 per cent. of tin; more antimony being added as the tin
is reduced, about 0.02 per cent. being added for each unit of tin reduced. I have
also discovered that bronze so alloyed may be cast, rolled, and drawn into sheets,
wire, tubes, and the like, that it is malleable, ductile, and resists torsion in a very
high degree, as well as the wrenching action of gunpowder in artillery.
I also find that the addition of about 1 to 1.3 per cent. of antimony to bronze
bearing metal materially increases its durability.
I also find that alloys of bronze, as above described, containing from '/, to 1/, per
cent. of antimony resist the action of sea water and acids in a remarkable degree.
In order to obtain constant results I recommend that best selected copper and
fine tin should be used, and that the antimony should be added in the form of an
alloy of copper and antimony. I have used an alloy of 70 copper and 30 antimony
with success. Some coppers contain antimony naturally, and having been analysed
may be used to introduce the antimony, but I recommend the use of pure metals.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Henry Hussey Vivian in the Great Seal Patent Office on the
27th January 1882.
HENRY HUSSEY VIVIAN, of Park Wern, Swansea, in the County of Glamorgan,
M.P. "IMPROVEMENTS IN THE MANUFACTURE OF BRONZE."
This Invention has for its object improvements in the manufacture of bronze.
Generally speaking, the admixture of even a small proportion of antimony with
copper is very injurious to the qualities of the latter metal, especially when used
as an alloy with zinc to produce brass, and consequently every care is taken
by the copper smelter to get rid of the impurity; but I have found that when
copper is alloyed with tin to form bronze, the influence of antimony in due
proportion is no longer injurious.
On the contrary, I find that by an addition of antimony I am able to increase
the strength, durability, hardness, and tenacity of alloys of tin and copper called
bronze, so as to impart to the alloy the characteristics desired according to the use
for which it is destined.
.
I have discovered that the addition of from one third to one fifth per cent. of
antimony adds materially to the strength of bronze consisting of from 93 to 96 per
cent. of copper, and 7 to 4 per cent. of tin; more antimony being added as the tin
is reduced, about 0·03 per cent. being added for each unit of tin reduced. I have
also discovered that bronze so alloyed may be cast, rolled, and drawn into sheets,
wire, tubes, and the like, that it is malleable, ductile, and resists torsion in a very
high degree, as well as the rending action of gunpowder in artillery, and the action
of sea water and acid solutions.
I also find that the addition of from 1 to 2 per cent. of antimony to bronze
bearing metal materially increases its durability and reduces the friction of moving
parts.
In order to obtain constant results I recommend that best selected copper and
fine tin should be used, and that the antimony should be added in the form of an
alloy of copper and antimony. I have used an alloy of 70 copper and 30 antimony
with success. Some coppers contain antimony naturally, and having been analysed
may be used to introduce the antimony, but I recommend the use of pure metals.
In practice I proceed as follows:-
-
I first make an alloy-of-copper-and-antimony_in_any_convenient proportions.
I have alloyed 70 of copper with 30 of antimony. I melt the copper in a plumbago
pot, and then gradually add the antimony; after stirring, the contents are allowed
to solidify in the pot to avoid the loss of antimony consequent on pouring. A
little charcoal is used in the melting, to cover the copper. To make the final alloy
I first melt the copper by itself until it reaches the boiling point (the boiling point
is indicated by the tremulous motion of a metal rod when inserted in the molten
copper) and then add the tin and the antimony alloy first described, well stirring
the metal at the time and then bring it again to the "boiling point"; it is then
taken from the furnace and well stirred before pouring into the moulds, which are
dressed over with resin, oil, and charcoal dust, or in some cases with tar. When
casting ingots for rolling, the moulds should be made slightly concave to allow for
shrinking of the metal in cooling and prevent the centre of the ingot from being
hollow.
I have also formed the alloy by adding tin and antimony directly to molten
copper without forming a primary alloy, as above described.
The best mixture I have found for tensile strength is―
Copper,
Another good mixture is-
Copper, 95-74;
antimony, * 100.
tin, 3-96 ;
antimony, 30=100.

page_text: It will be seen that in the latter mixture the antimony has been increased 06,
while the tin has decreased 2 per cent. or 03 per unit.
An excellent mixture for bearings is—
Copper, 83;
There are other good mixtures, as―
Copper, 86-38;
Copper, 85.70;
Also, Copper, 85;
tin, 1550;
antimony, 1·50=100.
tio, 12.30;
antimony, 1.32.
tin, 13;
antimony, 1.30.
tin, 13-70;
antimony, 1.30.
Having thus described the nature of my said Invention, and the manner of
performing the same, I would have it understood that I claim,—-
First. My improved bronze, to which antimony imparts strength, durability,
hardness, tenacity, and resistance to corrosion, and which is suitable to be cast,
rolled, and drawn, as herein described.
Second. My improved bearing bronze, substantially as described.
In witness whereof, I, the said Henry Hussey Vivian, have hereunto set
my hand and seal, this Nineteenth day of January, in the year of our
Lord One thousand eight hundred and eighty two.