IMPROVEMENTS IN THE MANUFACTURE OF STEEL
Year: 1876

page_text: LETTERS PATENT to Julius Baur, of the City of Brooklyn, in the County of
Kings, and State of New York, in the United States of America, but at present
of 23, Southampton Buildings, in the County of Middlesex, for the Invention
of "IMPROVEMENTS IN THE MANUFACTURE OF STEEL."
Sealed the 24th March 1876, and dated the 31st January 1876.
PROVISIONAL SPECIFICATION left by the said Julius Baur at the Office
of the Commissioners of Patents on the 31st January 1876.
JULIUS BAUR, of the City of Brooklyn, in the County of Kings, and State of
New York, in the United States of America, but at present of 23, Southampton
"IMPROVEMENTS IN THE MANUFACTURE OF
Buildings, in the County of Middlesex.
STEEL."
The Invention relates to improvements in the manufacture of steel, having
metallic chromium combined therewith, by means of which such descriptions of
steel can be produced in crucibles, or in any open hearth or puddling furnace, or in
the "Bessemer converter," as has before been proposed, of a character superior to
that made by any other known process.
are
The difficulties heretofore experienced in manufacturing "chrome steel"
entirely obviated and the cost of production materially lessened by the use of the
process of manufacture herein-after referred to, as it enables steel to be manu-
facturd which is not liable to become honeycombed in the ingot, which results in
the production of seamy steel, from which cause considerable loss has heretofore
been experienced in making chrome steel.
The difficulties heretofore experienced in introducing chrome steel, which are
chiefly owing to the fact that unless hardened at a much lower heat than carbon
steel it water cracks and becomes worthless, are obviated, inasmuch as the steel
made by my improved process can be hardened at any heat.
It has been before proposed to produce steel by the combination with the steel-
making iron of a mixture of oxide of chromium, oxide of manganese, and oxide of
iron, or ores of those metals, but this process was found in practice to be defective in
consequence of the imperfect reduction of the ores or oxides of chrome and man-
ganese, and consequent unequal combination of those metals with the steel-making

page_text: iron; it was in fact found that the oxides or ores of chromium and manganese
mainly passed off with the flux.
Now my present Invention relates to a new process of manufacture, wherein an
alloy of iron, chromium, and manganium combined in proper proportions is used,
the alloy being added in due proportions with or without carbon, as may be desired,
to the charge of steel-making iron so as to convert the same into steel.
In carrying the said Invention into effect I prepare, as herein-after described the
said alloy with reference to the kind and quality of the steel to be produced, and
the proportions of chromium, manganium, iron, and carbon used must be adapted
and varied according to the necessities of the case and the quality of steel required.
I give herewith, for example, the composition of two alloys designated respectively
A and B, the former containing, as will be seen, the greater per-centage of chromium.
These alloys may be called ferro-chromium-manganium alloys.
In preparing the alloy A I proceed as follows:-I place in a crucible about 10 lbs.
of chrome ore or oxide of chromium, about 5 lbs. of manganese ore or peroxide of
manganese, about 1/2 lbs. of borax, and about 3 lbs. of graphite, all finely pulverized
and intimately mixed. On the top of this mixture I place about 15 lbs. of suitable
metallic iron, as nearly pure as possible. The crucible is then placed in a proper
furnace, and the heat gradually increased to the proper melting point, when the iron,
chromium, and manganium will be found to have melted and combined into a solid
mass or cake of alloy, which can be granulated if desired by pouring it into water
instead of into a mould.
Alloy B is prepared in the same manner, and differs only in the proportions of
the ingredients. In preparing it I take about 71/2 lbs. _chrome ore or oxide of
chromium, about 7%, lbs. of peroxide of manganese or manganese ore, the quantities
of borax, graphite, and iron remaining the same as in alloy A.
It is obvious that the proportions of chrome and manganese in the alloys, or the
quantity of alloy used and of the carbon, must be varied according to the nature
and quality of the iron used for making the steel, but very good results are obtained
from the following examples melted in crucibles :-

page_text: accordingly; or, if preferred, by a proper change in the proportions of chrome and
manganese by reducing the quantity of the alloy or of the manganium in the alloy,
according to the excess of carbon that may be present in the steel-making iron, or,
vice versa, in the alloy used, or by increasing or diminishing the quantity of the
alloy.
In some cases the proportions before given may be considerably varied for pro-
ducing particular qualities of hard or soft steel for special purpose, but when a less
quantity than 3 oz. of the compound or alloy B is used to 50 lbs. of such iron as I
have specified, the steel cannot be properly hardened; and when more than 9 lbs.
of the alloy is used to 50 lbs. of the same quality of iron, using by preference
alloy A, the steel produced becomes too hard and loses its malleability, the latter
quantities being used only to produce steels for special purposes which require the
greatest resistance to compressive force and to heat. In this case iron containing a
minimum of carbon is to be preferred.
When inuch less than 5 oz. of either alloy is used to 50 lbs. of said steel-making
iron, gun or homogeneous steel only is produced. The quantity of the alloy may
however be reduced as low as about 3 oz. to the 50 lbs., and practicable and valuable
effect obtained, but below that little or no effect is produced.
The Bessemer metal is greatly improved by the use of the said alloy, which is to
be employed in the same manner as spiegel eisen, alloy B being better adapted for
the purpose than alloy A. The quantity of alloy and carbon to be added depends
upon the steel making iron used and the character of steel it is desired to produce,
and will vary from about 21/2 per cent. to about 10 per cent of alloy B.
In using the said alloy in the open hearth furnace I add it at the same period,
in the same manner, and in the same proportion that it is added in the Bessemer
converter.
In the puddling process I melt the alloy with the pig iron, and continue the work
as usual, but as a portion of the chrome and manganese is lost by oxidation, I use
about double the quantity or proportion of alloy used in the Bessemer process.
It will be seen from the description of my process already given that ferro-
chromium and ferro-manganese, or spiegel eisen rich in manganium, combined in
proper proportions, may be substituted for the "ferro-chromium-manganium alloy
described above, and may be employed without changing the process or the results
to be attained, as by the combination of ferro-chromium with ferro-manganese in
proper proportions "ferro-chromium-manganium" is produced.
"
I have described above a process for steel making by which ferro-chromium-
nanganium is used in the form of an alloy, as it is the only practicable manner in
which chromium and manganium can be combined with iron so as to produce steel
in the Bessemer converter or in the puddling furnace; it is also more certain, and
therefore cheaper, and in every way preferable for the production of steel in an open
hearth furnace or in crucibles, although the combination of such metals with the
steel-making iron can be effected in a more or less imperfect manner by using the
oxides of chromium and manganium in connection with borax and graphite in
the open hearth or puddling furnace, as described in a Provisional Specification filed
by me, on the 29th day of January 1876.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Julius Baur in the Great Seal Patent Office on the 31st July 1876.
JULIUS BAUR, of the City of Brooklyn, in the County of Kings, and State of
New York, in the United States of America, but at present of 23, Southampton
Buildings, in the County of Middlesex. "IMPROVEMENTS IN THE MANUFACTURE OF
STEEL."
The Invention relates to improvements in the manufacture of steel, having
nctallic chromium combined therewith, by means of which such descriptions of

page_text: steel of the best quality can be produced in crucibles, or in any open hearth or
puddling furnace, or in the "Bessemer converter."
The difficulties heretofore experienced in manufacturing "chrome steel" are
obviated by my present Invention, and the cost of production materially lessened,
by the use of the process of manufacture herein-after referred to, as it enables steel
to be manufactured which is not liable to become honeycombed in the ingot, which
results in the production of scamy steel, from which cause considerable loss has
heretofore been experienced in making chrome steel.
The difficulties heretofore experienced in introducing chrome steel may be said to
be chiefly owing to the fact that unless hardened at a much lower heat than carbon
steel it water cracks and becomes worthless; these will no longer form an obstacle,
inasmuch as the steel made by my improved process can be hardened at any heat.
It has been before proposed to produce steel by the combination with the steel-
making iron of a mixture of oxide of chromium, oxide of manganese, and oxide of
iron, or ores of those metals, but this process was found in practise to be in some
cases defective in consequence of the imperfect reduction of the ores or oxides of
chrome and manganese, and consequent unequal combination of those metals with
the steel-making iron; it was in fact found that the oxides or ores of chromium and
manganese mainly passed off with the flux.
Nowiny present Invention relates to a new process of manufacture wherein an
alloy of iron, chromium, and manganium combined in proper proportions is used,
the alloy being added in due proportions (with or without carbon as may be desired)
to the charge of steel-making iron so as to convert the same into steel.
In carrying the said Invention into effect I prepare, as herein-after described, the
said alloy with reference to the kind and quality of the steel to be produced, and
the proportions of chromium, manganium, iron, and carbon used must be adapted
and varied according to the necessities of the case and the quality of steel required.
I give herewith, for example, the composition of two alloys designated respectively
A and B, the former containing, as will be seen, the greater per-centage of chromium.
These alloys may be called ferro-chromium-manganium alloys.
.
In preparing the alloy A. I proceed as follows:-I place in a crucible about 10 lbs.
of chrome ore or oxide of chromium, about 5 lbs. of manganese ore or peroxide of
manganese, about 1/2 lbs. of borax, and about 3 lbs. of graphite, all finely pul-
verized and intimately mixed. On the top of this mixture I place about 15 lbs. of
suitable metallic iron, as nearly pure as possible. The crucible is then placed in a
proper furnace, and the heat gradually increased to the proper melting point, when
the iron, chromium, and magnanium will be found to have melted and combined
into a solid mass or cake of alloy, which can be granulated if desired by pouring it
into water instead of into a mould.
Alloy B is prepared in the same manner, and differs only in the proportions of
the ingredients. In preparing it I take about 71/2 lbs. chrome ore or oxide of
chromium, about 7 1/2 lbs. of peroxide of manganese or manganese ore, the quantities
of borax, graphite, and iron remaining the same as in alloy A.
It is obvious that the proportions of chrome and manganese in the alloys, or the
quantity of alloy used and of the carbon, must be varied according to the nature
and quality of the iron used for making the steel, but very good results are obtained
from the following examples melted-in-crucibles:-
1. 50 lbs. steel-making iron.
12 oz. alloy At
2 oz. carbon (charcoal).
2. 50 lbs. steel-making iron.
12 oz. alloy B.
2 oz. carbon (charcoal).
3. 50 lbs. steel-making iron.
24 oz. alloy B.
4. 50 lbs. steel-inaking iron.
24 oz. alloy A.
For cutlery, axes, saws, spring steel,
and other similar purposes.
For cold chisels, stone-cutters' tools,
hammers, and other similar pur-
poses.
For turning and planing tools, and
other similar purposes.
For heading dies and other similar
purposes.

page_text: In case any sulphur exists either in the steel-making iron or in the fuel I add
about 3 oz. of common salt (chloride of sodium) to each crucible charge to protect the
metal from the sulphurous or carbonic oxide gases, and to eliminate any sulphur
from the iron.
No oxide of manganese is necessary as a flux in producing steel according to this
my present Invention.
In preparing the above examples I have assumed that the steel-making iron used
contains about 0-22 per cent. of carbon, but if iron either higher or lower in carbon
is used, the amount of carbon added to the charge should be increased or diminished
accordingly; or, if preferred, by a proper change in the proportions of chrome and
manganese by reducing the quantity of the alloy or of the manganium in the alloy
according to the excess of carbon that may be present in the steel-making iron, or,
vice versa, in the alloy used, or by increasing or diminishing the quantity of the
alloy.
In some cases the proportions before given may be considerably varied for pro-
ducing particular qualities of hard or soft steel for special purposes, but when a less
quantity than 3 oz. of the compound or alloy B is used to 50 lbs..of such iron as I
liave specified, the steel cannot be properly hardened; and when more than 9 lbs.
of the alloy is used to 50 lbs. of the same quality of iron, using by preference
alloy A, the steel produced becomes too hard and loses its malleability, the latter
quantities being used only to produce steels for special purposes which require the
greatest resistance to compressive force and to heat. In this case iron containing a
minimum of carbon is to be preferred. If however the steel-making iron should
contain as low a per-centage of carbon as 0.05, as much as 12 lbs. of the alloy inay
be used to the said charge.
When much less than 5 oz. of either alloy is used to 50 lbs. of said steel-making
iron, gun or homogeneous steel only is produced. The quantity of the alloy may
however be reduced as low as about 3 oz. to the 50 lbs., and practicable and valuable
effect obtained, but below that little or no effect is produced.
The Bessemer metal is greatly improved by the use of the said alloy, which is to
be employed in the same manner as spiegel eisen, alloy B being better adapted for
the purpose than alloy A. The quantity of alloy and carbon to be added depends
upon the steel-making iron used and the character of steel it is desired to produce,
and will vary from about 21 per cent. to about 10 per cent. of alloy B.
In using the said alloy in the open hearth furnace I add it at the same period,
in the same manner, and in the same proportion that it is added in the Bessemer
converter.
In the puddling process I melt the alloy with the pig iron, and continue the work
as usual, but as a portion of the chrome and manganese is lost by oxidation, I use
about double the quantity or proportion of alloy used in the Bessemer process.
It will be seen from the description of my process already given that ferro-
chromium and ferro-manganese, or spiegel eisen rich in manganium, combined in
proper proportions, may be substituted for the "ferro-chromium-manganium" alloy
described above, and may be employed without changing the process or the results
to be attained, as by the combination of ferro-chromium with ferro-manganese in
proper proportions "ferro-chromium-manganium" is produced.
I have described above a process for steel making by which "ferro-chromium-
manganium" is used in the form of an alloy, as it is I believe the only practicable
manner in which chromium and manganium can be combined with iron so as to
produce steel in the Bessemer converter or in the puddling furnace; it is also more
certain and therefore cheaper and in every way preferable for the production of steel
in an open hearth furnace or in crucibles, although the combination of such metals
with the steel-making iron can be effected in a more or less imperfect manner by
using the oxides of chromium and manganium in connection with borax and graphite
in the open hearth or puddling furnace, as described in a Provisional Specification
filed by me on the Twenty-ninth day of January, One thousand eight hundred and
seventy-six.

page_text: Having thus described the nature of my said Invention and the manner in which
the same is carried into effect, I would have it understood that what I claim is, the
manufacture of steel by the combination with the steel-making iron in suitable pro-
portions of an alloy of chromium, manganium, and iron, or of the requisite propor-
tions of ferro-chromium and ferro-manganium, substantially as described.
In witness whereof, I, the said Julius Baur, have hereunto set my hand and
seal, this Twenty-seventh day of July, in the year of our Lord One thousand
eight hundred and seventy-six.
TTTT TITOL
דזמד
JULIUS BAUR. (L.S.)