AN IMPROVEMENT OR IMPROVE- PROVISIONAL SPECIFICATION
Year: 1883

page_text: LETTERS PATENT to Frederick William Martino of Sheffield in the County
of York Manufacturer for an Invention of "AN IMPROVEMENT OR IMPROVE-
PROVISIONAL SPECIFICATION left by the said. Frederick William Martino
at the Office of the Commissioners of Patents on the 11th July 1883.
FREDERICK WILLIAM MARTINO of Sheffield in the County of York Manu-
facturer "AN IMPROVEMENT OR IMPROVEMENTS IN THE MANUFACTURE OF ALLOYS
OF TUNGSTEN
"
The metal tungsten requires for its fusion so high a temperature that it is
impracticable to alloy it with other metals in the ordinary way that is by adding
the metals together in the required proportions and melting them in a crucible or
melting pot.
My invention consists of the improvement or improvements hereinafter described
in the manufacture of alloys of tungsten whereby alloys of tungsten with copper
tin and zinc may be readily manufactured
I take a mixture of metallic tungsten and phosphide of calcium and fuse the
mixture in a crucible preferably a plumbago crucible. I keep the crucible well
covered with a lid and the contents of the crucible covered with a layer of
powdered charcoal during the fusion of the mixture of tungsten and phosphide
of calcium. By the action of the phosphide of calcium on tungsten a regulus
of phosphide of tungsten is produced. I add this phosphide of tungsten to metallic
copper and melt the mixture in a plumbago crucible the mixture being covered
with a layer of powdered charcoal. In this way I obtain an alloy of tungsten and
copper the said alloy also containing phosphorus. By the addition to this alloy of
tungsten copper and phosphorus of an alloy of copper and tin or copper tin and
zinc I produce a series of alloys having such colours and possessing such ductility

page_text: and malleability as fit them for the manufacture of a variety of articles such
for example as spoons forks fish and desert knives as well as vessels of various
kinds.
Although I find phosphide of calcium to answer perfectly in the manufacture
of phosphide of tungsten yet I do not limit myself thereto as most of the phosphides
of the earthy and alkaline metals may be used for that purpose. And although
I have only described the use of the said phosphide of tungsten in the manufacture
of alloys containing copper tin and zinc yet I wish it to be understood that the
phosphide of tungsten may be employed for the manufacture of alloys of tungsten
generally.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by.
the said Frederick William Martino in the Patent Office on the 4th January
1884.
FREDERICK WILLIAM MARTINO of Sheffield in the County of York Manu-
facturer «
AN IMPROVEMENT OR IMPROVEMENTS IN THE MANUFACTURE OF ALLOYS
OF TUNGSTEN
"
1
The metal tungsten requires for its fusion so high a temperature that it is
impracticable to alloy it with other metals in the ordinary way, that is, by adding
the metals together in the required proportions and melting them in a crucible or
melting pot.
My invention consists of the improvement or improvements hereinafter described
in the manufacture of alloys of tungsten, whereby alloys of tungsten with copper,
tin and zinc and other metals may be readily manufactured.
I take a mixture of metallic tungsten and phosphide of calcium and fuse the
mixture in a crucible preferably a plumbago crucible. I keep the crucible well
covered with a lid and the contents of the crucible covered with a layer of powdered
charcoal during the fusion of the mixture of tungsten and phosphide of calcium.
By the action of the phosphide of calcium on the tungsten, a regulus of phosphide
of tungsten is produced. I add this phosphide of tungsten to metallic copper or
to Phosphor bronze and melt the mixture in a plumbago crucible, the mixture
being covered with a layer of powdered charcoal. In this way I obtain an alloy
of tungsten and copper the said alloy also containing phosphorus. By the addition
to this alloy of tungsten, copper and phosphorus, of an alloy of copper and tin or
copper and zinc, I produce a series of alloys having such colours and possessing
such ductility and malleability as fit them for the manufacture of a variety of
articles such, for example, as spoons forks fish and dessert knives as well as vessels
of various kinds. Although I have only described the use of the said phosphide of
tungsten in the manufacture of alloys containing copper, tin and zinc yet I wish it
to be understood that the phosphide of tungsten may be employed for the manu-
facture of alloys of tungsten generally. Phosphide of calcium and phosphor bronze
may both be obtained in commerce and I therefore do not consider it necessary to
describe the same.
Most of the phosphides of the earthy and alkaline metals may be used in place
of phosphide of calcium for the production of phosphide of tungsten but I prefer
the use of phosphide of calcium to any other phosphide for the production of
phosphide of tungsten.
Or I make the phosphide of tungsten by the direct combination of phosphorus
with metallic tungsten instead of employing phosphide of calcium or other
phosphides for that purpose.
In making phosphide of tungsten by the direct combination of its elements,
I employ red phosphorus, that is, amorphous phosphorus. This is a well known
article of commerce. I take forty five parts by weight of metallic tungsten in the
form of a black powder and forty five parts by weight of amorphous phosphorus,
which is also in powder and ten parts by weight of metallic copper and I melt the
mixture in a Hessian or graphite crucible by the application of a low red heat.
I prefer to cover the mixture in the crucible with a layer of fine sand (silica) and
powdered charcoal closely pressed on it. By the use of the said layer of silica
and powdered charcoal and by raising the temperature of the crucible as quickly
as is practicable, the loss of phosphorus by volatilization is small The layer of fine
sand may be dispensed with but in that case an excess of amorphous phosphorus

page_text: must be employed. The phosphide of tungsten may also be obtained by heating
a mixture of amorphous phosphorus with tungstic acid. In this case, the mixture
of tungstic acid and amorphous phosphorus is covered with a layer of finely
powdered charcoal which on the heating of the crucible and its contents effects
the deoxidation of the tungstic acid,, the liberated metal tungsten combining with
the phosphorus.
When I employ this method I add forty five parts by weight of amorphous
phosphorus to fifty five parts by weight of tungstic acid and ten parts by weight
of metallic copper but in this case as in all cases where amorphous phosphorus is
employed to produce phosphide of tungsten, amorphous phosphorus in excess of the
quantity specified may be employed as in the making of the phosphide of tungsten
or the making of tungsten alloys by the use of the. phosphide of tungsten any
excess of phosphorus is volatilized or oxidised.
The phosphide of tungsten obtained in any of the ways described. is not a definite
compound but generally contains an excess of phosphorus.
When it is wished to make an alloy containing an exact percentage of tungsten
a chemical analysis of the phosphide of tungsten employed must be made and the
quantity of tungsten contained in it calculated in the ordinary way. But for
general purposes this is unnecessary as in the more ordinary alloys of tungsten
with copper and zinc or with German silver, the resulting compound exhibits
physical properties which are a better guide than chemical analysis. For example,
in either of, the alloys of tungsten last referred to an excess of tungsten gives a
hardness and imperfect ductility and the testing of the alloy by filing and
hammering shows whether or not the alloy contains an excess of tungsten.
In case the alloy is too hard and is wanting in ductility it is remelted and more
copper and spelter or more German silver are or is added thereto..
Alloys of tungsten have little tendency to tarnish and by adding in the ways
hereinafter described phosphide of tungsten to brass that is, an alloy, of copper and
zinc and to German silver, that is, an alloy of nickel, copper and zinc, these alloys
remain bright or untarnished under atmospheric influences a much longer time
than ordinary brass and German silver. The addition of a small quantity of.
phosphide of tungsten has a very great effect in preventing the liability to tarnish.
The addition of from one to two percentum of phosphide of tungsten to brass or
German silver is enough for this purpose.
In alloying brass with tungsten I first combine the phosphide of tungsten with
a portion of the copper of which the brass is to be made and afterwards alloy the
compound thus obtained with the remaining portion of the copper and finally add
the necessary proportion of zinc.
In alloying German silver with tungsten I first combine the phosphide of
tungsten with a portion of the copper of the German silver to be made. I then
alloy this compound with a further quantity of the copper and part of the nickel
and to this alloy I add part of the zinc. I afterwards add to this alloy the
remaining proportions of the copper, nickel and zinc in the order named.
In making alloys of tungsten by the use of phosphide of tungsten I employ
as a flux, borax with the addition of a little carbonate of lime and expose the
charged crucible uncovered to heat in an oxidizing atmosphere, that is, the furnace
holes are opened so that there shall be free access of air and consequently an
oxidizing atmosphere in the crucible. When the tungsten alloy is melted under
these conditions a large part of the tungsten and all or nearly all the phosphorus
oxidize and pass into the slag or scoria but have produced before their elimination
the desired change in the physical' character of the alloy, a change somewhat
analogous to that produced by manganese on steel and magnesiuin on nickel.
After the alloy of tungsten has been formed by melting together phosphide of
tungsten and the other metals, of the alloy under the conditions described, the
melted alloy is poured into ingot or pig moulds. In forming the said alloy I do
not stir the mixture but after the contents of the crucible 'have been thoroughly

page_text: melted for a short time, I take the crucible from the furnace, skim off the scum
with a red hot graphite or well burned clay rod or scraper and pour the contents
into ingot moulds as before described. If after the ingots have cooled the surface
of the alloy is quite bright the alloy is fit for commercial purposes and is remelted
and cast into ingots. If however the ingots are covered with a gritty greyish scum
which cannot be removed by hammering or scraping, the alloy must be remelted
with flux as hereinbefore described and that operation repeated if necessary until
the cast ingots have a bright surface.
After a little experience the necessity for the remeltings described of the alloy
of tungsten rarely arises as the required amount of phosphide of tungsten to be
added to the other metals of the alloy will have been suggested by the experience
referred to and the operator will generally obtain an alloy both malleable and
ductile without the necessity for remelting.
Besides the property which tungsten has of diminishing the tendency to
oxidation or tarnish of alloys into which it enters, it has also the property of
giving to alloys consisting mainly of copper, a gold like appearance producing
a bronze not only gold like in colour but very little liable to tarnish. A bronze
having the properties last described is formed by the use of from eighty to ninety
parts by weight of copper; three parts by weight of tin; 6 parts by weight of zinc
and one part by weight of Bismuth, with the addition of ten parts by weight of
phosphide of tungsten. As however a large part of the tungsten and phosphorus
is eliminated in the alloying of the metals, the resulting alloy contains a much less
quantity of tungsten and phosphorus.
Having now described the nature of my invention and the manner in which
the same is to be performed I wish it to be understood that I do not limit myself
to the precise details herein described as the same may be varied without departing
from the nature of my invention.
But I claim as my invention of "An improvement or improvements in the
manufacture of alloys of tungsten." The methods herein before described of
manufacturing alloys of tungsten by the use of phosphide of tungsten made either
by the fusion of phosphide of calcium or other earthy or alkaline phosphides, with
metallic tungsten, or by the fusion of red or amorphous phosphorus with metallic
tungsten, or by the fusion of tungstic acid with amorphous phosphorus in presence
of carbonaceous matter substantially as hereinbefore described.
In witness whereof I the said Frederick William.Martino have hereunto set my
hand and seal this Twenty second day of December in the year of our Lord one
thousand eight hundred and eighty-three
TAניזגז נוה
TTT
Witness,
GEORGE HOLLOWOOD
199 Arundel Street.
Sheffield
וזבז ווה
TREUERUD
WILLIAM
OUTTATUM
(F.D.)