Improvements in the Manufacture of Bronze.
Year: 1888

page_text: Date of Application, 8th Feb., 1888
Complete Specification Left. 8th Nov., 1888
Complete Specification Accepted. 14th Dec.,
1888
[Communicated from abroad by AUGUSTIN SENTEX, CONSTANTIN MARéohal, and
ALFRED SAUNIER, all of Paris, in the Republic of France.]
Improvements in the Manufacture of Bronze.
I, WILLIAM HENRY BECK, of 115 Cannon Street, in the City of London, Consulting
Engineer, and Patent Agent do hereby declare the nature of this invention to be as
follows:-
Heretofore, bronze containing a large proportion of tin has been only partially
malleable; it cracks in rolling, splits in the heating furnace, and plates or flakes of tin
often appear at the surface of plates made from such material.
These defects are caused by the want of homogeneity due to the tendency of the tin
to separate from the copper when in the fused state. They have been overcome in
sand castings, such as bells, guns, bearings and so forth, by the addition of one or two
per cent. of phosphorous which imparts hardness and homogeneity to the metal, and
serves as a bond or solder for the metals composing the bronze; but bronze made
in that way is always brittle and unsuitable for being rolled or drawn into wire.
By the process forming the subject of the present invention, malleable and ductile
bronze can be produced containing a large proportion of tin. This result is effected
by submitting the alloys, as well as the metals composing them, to a series of chemical
operations which completely modify their properties.
Although the proportions of the metals composing the alloy may vary considerably
according to the properties it is desired to impart to the alloy, such as malleability,
ductility, tenacity, hardness, sonorosity etcetera, the process remains the same unless
the metal is not required to fulfil certain conditions such as inoxydizability for
example, in which case one or more of the operations may be omitted.
By way of example I will now proceed to describe the manufacture, in accordance
with this invention, of bronze of as perfect a quality as possible, and composed of
about 10 kilogrammes of copper to 1 kilogrammes of tin.
The metals to be employed must be of the best quality and as pure as possible.

page_text: •
The tin is prepared by introducing into the fused metal 12 to 15 per cent. of salt of
nitre. As soon as the salt is melted by contact with the tin, the mixture is thoroughly
agitated and then allowed to cool. The impurities of the metal are taken up by the
sali, which solidifies in cooling, and are easily separated.
The copper is put into a crucible and the temperature raised to the melting point.
At that moment 50 grammes of a mixture of equal parts of nitrate of potash and of
cyanide of potassium are to be added for the double purpose of reducing the oxides,
and of fattening the metal. After complete fusion of the copper, 25 grammes of
bitartrate of potash, mixed with an equal quantity of cyanide of potassium, are to be
introduced for the same purpose. The tin prepared and purified as above described,
is then added to the copper after poling or stirring with green wood. At that moment
50 grammes of a mixture of equal parts of sal ammoniac, or hydrochlorate of ammonia,
and of cyanide of potassium, are introduced into the crucible, then an instant after one
gramme of phosphuret of copper to impart mildness to the metal, and about 20 grammes
of Marseilles soap which fattens the metal still more.
Finally, at the moment of running the liquid metal, after poling or stirring with
green wood, a gramme of sodium is introduced which alloys with the mass, further
reducing the oxides, and, by its affinity for the tin, sal ammoniac and other products,
renders the alloy inoxydizable. This inoxydizability increases as the proportion of tin
is increased.
The quantity of phosphorous and sodium may be increased if the proportion of tin be
reduced.
Bars or plates of bronze cast in this manner are entirely free from cracks and blow
holes, and if prepared in the ordinary way they may be rolled and drawn with the
greatest ease. The metal obtained has the appearance and sonorosity of gold, and
resists all atmospheric action.
The same metal when cast in sand, and which in that case may be richer in tin,
gives fine castings which, when pickled, resist oxydation as well as the alloys of
gold.
Dated this 8th day of February 1888.

page_text: I, WILLIAM HENRY BECK, of 115 Cannon Street, in the City of Loudon, Consulting
Engineer and 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 ascer-
tained in and by the following statement:-
Heretofore bronze containing a large proportion of tin has been only partially
malleable, it cracks in rolling, splits in the heating furnace and plates or flakes of tin
often appear at the surface of plates made from such material.
These defects are caused by the want of homogeneity due to the tendency of the
tin to separate from the copper when in the fused state. They have been overcome
in sand castings such as bells, guns, bearings and so forth by the addition of one or
two per cent. of phosphorous which imparts hardness and homogeneity to the metal,
and serves as a bond or solder for the metals composing the bronze; but bronze
made in that way is always brittle and unsuitable for being rolled or drawn into
wire.
•
By the process forming the subject of the present invention malleable and ductile
bronze can be produced containing a large proportion of tin. This result is effected by
submitting the alloys as well as the metals composing them, to a series of chemical
operations which completely modify their properties.
Although the proportions of the metals composing the alloy may vary considerably
according to the properties it is desired to impart to the alloy, such as malleability,
ductility, tenacity, hardness, sonorosity, etcetera, the process remains the same unless
the metal is not required to fulfil certain conditions such as inoxydizability for example,
in which case one or more of the operations may be omitted.
By way of example I will now proceed to describe the manufacture, in accordance
with this invention, of bronze of as perfect a quality as possible, and composed of
about 10 kilogrammes of copper to 14 kilogrammes of tin.
The metals to be employed must be of the best quality and as pure as possible.
The tin is prepared by introducing into the fused metal 12 to 15 per cent. of salt
of nitre. As soon as the salt is melted by contact with the tin the mixture is thoroughly
agitated and then allowed to cool. The impurities of the metal are taken up by the
salt, which solidifies in cooling, and are easily separated.
The copper is put into a crucible and the temperature raised to the melting point.
At that monent 50 grammes of a mixture of equal parts of nitrate of potash and of
cyanide of potassium are to be added for the double purpose of reducing the oxides,
and of fattening the metal. After complete fusion of the copper 25 grammes of bitar-
trate of potash mixed with an equal quantity of cyanide of potassium are to be intro-
duced for the same purpose. The tin prepared and purified as above described, is then
added to the copper after poling or stirring with green wood. At that moment
50 grammes of a mixture of equal parts of sal ammoniac or hydrochlorate of animonia

page_text: and of cyanide of potassium are introduced into the crucible, then an instant after one
gramme of phosphuret of copper to impart mildness to the metal, and about
20 grammes of Marseilles soap which fattens the metal still more.
Finally at the moment of running the liquid metal, after poling or stirring with
green wood, a gramme of sodium is introduced which alloys with the mass, further
reducing the oxides, and, by its affinity for the tin, sal ammoniac and other products
renders the alloy inoxydizable. This inoxydizabilty increases as the proportion of tin
is increased.
The quantity of phosphorous and sodium may be increased if the proportion of tin
be reduced.
Bars or plates of bronzo cast in this manner are entirely free from cracks and blow
holes, and if prepared in the ordinary way they may be rolled and drawn with the greatest
ease. The metal obtained has the appearance and sonorosity of gold, and resists all
atmospheric action. The same metal when cast in sand, and which in that case may
be richer in tin, gives fine castings which when pickled resist oxydation, as well as
the alloys of gold.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what J
claim is:
First The process of manufacturing bronze, which consists in previously purifying
the tin by adding thereto, whilst it is in a state of fusion, a suitable proportion of salt
of nitre and then letting it cool, in melting the copper and maintaining it in a stato
of fusion and adding thereto nitrate of potash and cyanide of potassium, in adding to
the copper thus prepared, the previously purified tin, then introducing into the fused
alloy sal ammoniac or hydrochlorate of ammonia, cyanide of potassium, phosphuret of
copper, and Marseilles Soap, in adding sodium after poling or stirring with green
wood, and finally in casting the metal so treated into the required shape, as herein-
before described.
Second As a new manufacture, the bronze metal resulting from the mixture of
copper and tin, and the introduction into, and mixture therewith, of the materials
herein before mentioned, substantially as hereinbefore described.
Dated this 8th day of November A.D. 1888.
Dated this 8th day of November A.D. 1888.
W. H. BECK,
115, Cannon Street, London, E.().,
Applicant.