IMPROVEMENTS IN THE MANUFACTURE OF METAL CASTINGS
Year: 1868

page_text: LETTERS PATENT to Alexander Prince, of the Office for Patents,
4, Trafalgar Square, Charing Cross, in the County of Middlesex,
for the Invention of "IMPROVEMENTS IN THE MANUFACTURE OF METAL
CASTINGS." A communication from abroad by Edward L. Brown,
of the City of Philadelphia and State of Pennsylvania, United States
c A
Sealed the 4th December 1868, and dated the 5th June 1868.
PROVISIONAL SPECIFICATION left by the said Alexander Prince at
the Office of the Commissioners of Patents, with his Petition, on
the 5th June 1868.
I, ALEXANDER PRINCE, of the Office for Patents, 4, Trafalgar Square,
Charing Cross, in the County of Middlesex, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN THE MANUFACTURE OF
METAL CASTINGS," a communication to me from abroad by Edward L..
Brown, of the City of Philadelphia and State of Pennsylvania, United
States of America, to be as follows:--
This Invention relates to certain improvements in castings, where a
wrought metal core or interior mass is coated with cast metal in order
to impart to such castings additional strength to resist various strains
or concussions. Heretofore the wrought metal has been first coated
with tin or some other easily fused metal to act, first, as a solder or

page_text: means of union between the wrought and cast metal, and secondly, to
absorb a part of the heat of the cast metal, and thus prevent the crystal-
lization or granulation of the wrought metal; but by these means, in
order to have the fusible metal to act as a solder, a considerable
thickness of it must be used, and thus a layer of comparatively weaker
metal must necessarily intervene between the wrought metal and the
body of the cast metal. The fusible metal or alloy acting as a solder
does absorb some of the heat of the molten metal, but it melts in the
process and allows the cast metal, at a heat only slightly diminished,
to come in contact with the wrought metal.
This melting of the fusible metal produces various injurious results:-
1st. The wrought metal under the influence of the heat of the cast
metal in contact with it, is crystallized either entirely or partially, and
its fibre commensurately destroyed, and to a degree sufficient to
materially reduce its tensile strength.
2ndly. The tin or other metal or alloy, fusible at a heat below that of
the cast metal, is chemically decomposed in melting, and a gas or gases
generated, which being very volatile and elastic, must expand and force
their way into or through the molten metal. These gases form blow
holes and produce a cellular or spongy condition in the metal, which is
injurious. So also if wrought metal be used without any coating, either
heated or cold, polished or unpolished, the molten metal by its heat
decomposes the oxide on the surface of the wrought metal and releases
oxygen gas, and produces similar results, and prevent the close shrinkage
of the cast metal around the wrought metal.
Now, according to this Invention, instead of presenting to the molten
metal an easily fusible metal, a metal is presented which it is difficult
or impossible to melt at the degree of heat of the molten metal to be
poured about it. The wrought metal is first to be thoroughly cleansed
by means of acids or otherwise, and is then immediately and perfectly to
be coated with a non-oxidizable metal or substance very difficult to fuse,
and one that will melt only at a higher heat than the cast metal that is
to be poured about it. It is preferred to use nickel for this purpose, as
this melts only at an exceedingly high heat, much higher than that
of iron, and is almost impossible to fuse; other metals, such as
platinum, can be employed, and plumbago may be used. The coating
may be effected by means of a galvanic battery or other electric action,
or by means of heat or other suitable process. The wrought metal if

page_text: iron may first be coated with copper or other metal, for which iron has
a great affinity, to serve as a basis for the coating of the non-fusible
metal. The molten cast metal cannot, when it comes in contact in the
mould with the wrought metal thus prepared, melt this coating, and thus
cannot strike the wrought metal itself, and cannot impair the fibre of the
wrought metal; neither can blow holes or spongy texture be formed,
because there is no evolution of gas. The wrought metal to be coated
may be roughened or serrated to effect a more perfect cohesion.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Alexander Prince in the Great Seal Patent Office
on the 5th December 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
PRINCE, of the Office for Patents, 4, Trafalgar Square, Charing Cross,
in the County of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fifth day of June, in the year of
our Lord One thousand eight hundred and sixty-eight, in the thirty-
first year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Alexander Prince, Her special
licence that I, the said Alexander Prince, my executors, adminis-
trators, and assigns, or such others as I, the said Alexander Prince,
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
"IMPROVEMENTS IN THE MANUFACTURE OF METAL CASTINGS," a communication
to me from abroad by Edward L. Brown, of the City of Philadelphia, and
State of Pennsylvania, United States of America, upon the condition
(amongst others) that I, the said Alexander Prince, my executors or
administrators, by an instrument in writing under my, or their, or one
of their hands and seals, 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 immediately after the date
of the said Letters Patent.

page_text: NOW KNOW YE, that I, the said Alexander Prince, 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 :-
This Invention relates to certain improvements in castings where
wrought metal is combined with cast metal, in order to impart to such
cast metal additional strength, as well as to fix wrought metal in cast
metal. Hitherto wrought metal has been coated with tin, or some other
easily fusible metal, to act as a solder or means of union between the
wrought and cast metals. In order, however, to have the fusible metal
to act as a solder a considerable thickness of it must be used, and thus a
layer of comparatively weaker metal would intervene between the wrought
metal and the cast metal, thereby weakening the structure thus produced.
If wrought metal otherwise than polished, without coating, be used, either
heated or cold, the carbon of the molten cast metal seizes upon and
combines with the oxygen of the protoxide covering the surface of the
wrought metal, producing carbonic acid gas which fills the cast metal
with blow holes, causing a spongy texture, and as a consequence
rendering it unsound.
Now, according to this Invention, instead of presenting to the molten
metal an easily fusible metal, one is presented which it is difficult or
impossible to melt at the temperature of the molten metal to be poured
about it. The wrought iron or other metal is first to be thoroughly
cleansed by means of acids or otherwise, and is then to be immediately
and perfectly coated with a non-oxydisable metal or substance very
difficult to fuse. It is preferred to use nickel for this purpose, as this
metal melts only at an exceedingly high temperature. Other metals,
such as platinum or even plumbago, may be used. The coating may be
effected by metal or other material deposited by means of a galvanic or
other battery or other suitable process; or by the aid of heat, according
to the well known processes of depositing or coating metals with metals,
either by aid of electrical action or otherwise. The wrought metal, if
iron, may first be coated with copper or other material for which iron
has a great affinity, to serve as a basis for the coating of the non-fusible
metal. The melted cast-iron metal cannot, when it comes in contact
(in the mould) with the wrought metals thus prepared, melt this
coating, and consequently cannot strike or come in contact with the
wrought metal itself, and therefore blow holes causing a spongy texture
cannot be formed, there being no evolution of gas. The wrought metal

page_text: to be coated may be roughened or serrated with the object of effecting
a more perfect cohesion.
In accordance with this Invention it is evident that in all cases where
wrought metal is to be treated with cast metal, in order to manufacture
a casting, the process described will be more or less applicable; thus in
the manufacture of girders or other articles (where probably the
wrought iron should previously be subjected to the degree of strain it
would ultimately have to resist) the wrought iron core could be treated
with a coating of nickel or other metal possessing the requisite qualities,
previous to its subjection to the cast metal surrounding it.
So also in the construction of railway wheels, however formed, whether
partly built up or composed of wrought iron or steel, or a combination
thereof, or of other description of metal which require to be treated
ultimately with cast iron or cast metal, the process is equally applicable.
Having now described the nature of the said Invention, and in
what manner the same is to be performed, I claim as the Invention
secured to me (on behalf of my foreign correspondent) by the herein
in part recited Letters Patent, the improvements in the manufacture
of metal castings by means of the application to the wrought metal of
a coating of nickel or other metal possessing the requisite resisting
properties to the effects of molten cast metal in contact therewith,
whereby the wrought metal is protected from the hitherto injurious
effectsof the cast molten metal in contact with the wrought metal (in
the mould) substantially as and for the purposes herein specified.
In witness whereof, I, the said Alexander Prince, have hereunto
set my hand and seal, this Fifth day of December, in the year
of our Lord One thousand eight hundred and sixty-eight.
Witness,
0
J. C. H. SIEVIER,
Clerk to Messrs. Prince & Co.,
Office for Patents,
4, Trafalgar Square,
Charing Cross.
ALEXR. PRINCE. (L.S.)