Year: 1886

page_text: 1, KOBERT HADFIELD of Sheffield in the County of York, Steel Manufacturer
do hereby declare the nature of this invention to be as follows:-
This Invention has for its object the production and manufacture of a new steely
alloy or compound hereafter termed "Chrome Steel" the principal constituents
whereof are iron (ferrum) chromium-manganese and silicon.
Such chrome steel combines most of the properties of ordinary carbon steel with
special excellence and is of very high commercial value although comparatively
inexpensive to manufacture.
This economy in manufacture I effect by dispensing with the costly qualities of
iron heretofore employed for the production and manufacture of high class steels-
When desired however such costly qualities of iron may be employed in conjunction
with my improved treatment.
The condition of the iron which forms the basis of my improved chrome steel
and from which it is manufactured may be that of ordinary pig metal cast iron;
steel, wrought iron, steel or iron scrap or a mixture of all or any of them, and the
process or processes by which the. iron or steel is manufactured or reduced or
subsequently treated is immaterial the only necessary requirement being that the
iron before the addition of the chromium manganese and silicon should be sub-
stantially decarbonised by which I mean not necessarily devoid of carbon but that
the metal should be or should have been previously decarbonised wholly or to a
great extent-Hence my invention is applicable to the production and manufacture
of steel by means of the Bessemer, open hearth or other decarbonising and refining
processes or by means of the crucible processes; these processes being carried on in
the usual way as regards the Bessemer, open hearth, or kindred processes until the
metal under treatment is nearly or quite decarbonised when the requisite per
centages of chromium manganese and silicon are added while if the crucible process
be employed the chromium, manganese and silicon additions may be introduced at
any stage of the process."
The chromium, manganese and silicon are added thereto in suitable per centages
say for instance not less than three quarters of one per cent of chromium-one

page_text: tenth of one per cent of manganese-and a similar proportion of silicon―These per
centages vary in proportion however according to the resultant product desired to
be obtained.
The addition of the chromium manganese and silicon may be effected by any
Buitable means.
My chrome steel may be hardened and tempered in the ordinary manner when
requisite.
It combines with peculiar hardness and closeness of grain an extraordinary
capability of resisting high strains of compression.
3000
SHIRLEY BOWDEN,
33, Southampton Buildings, Holborn, London,
Agent for the Applicant.

page_text: I ROBERT HADFIELD of Sheffield Yorkshire Steel -Manufacturer do hereby
declare the nature of this 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 has for its object the production of a new steely alloy or com-
pound the principal constituents whereof are,-iron (ferrum) chromium, manganese
and silicon but which may also contain carbon as well as other ingredients such as
sulphur and phosphorus which may be present in the metal such alloy having most
of the qualities of ordinary carbon steel besides other qualities hereinafter mentioned
peculiar thereto-Such peculiar properties are chiefly derived from the presence of
certain percentages of chromium, manganese and silicon as hereinafter specified.
Such steely alloy or compound while possessing special excellence is comparatively
inexpensive to manufacture this economy arising from the fact that I dispense with
the costly qualities of iron heretofore employed for the production of high class
steels and employ instead all or any of the various substitutes presently mentioned―
I will now proceed to describe my invention and the means of carrying out the
same.
The condition of the iron which forms the basis of my improved steely alloy or
compound and from which it is produced may be that of any ordinary pig metal or
cast iron (such as is generally made from mineral coal)-used in the manufacture
of steel, or wrought iron, steel or iron scrap or a mixture of all or any of these and
the process or processes by which the iron or steel is manufactured or reduced or
subsequently treated may be of the ordinary kind the only necessary requirement
being that the iron before the addition of the chromium manganese and silicon
should have been practically decarbonised by any well known process though as
regards crucible products it is not absolutely necessary to so decarbonise it.
My improved process is applicable to the manufacture of steel by means of the
Bessemer, open hearth or other decarbonising and refining processes or by means
of the crucible process these processes being carried on in the usual way-As
regards the Bessemer or open hearth or kindred processes they should be carried
on until the metal is nearly or quite decarbonised when the requisite per centages
of chromium manganese and silicon are to be added thereto as hereinafter directed-
If the crucible process be employed the chromium manganese and silicon may be
introduced at any stage of the process.
Hitherto in the manufacture of high class steels it has been considered necessary
or at all events most advantageous to employ the best and most costly qualities of
iron-Now I have discovered that if chromium together with manganese and
silicon are present in sufficient quantities say of chromium 75 per cent to 7 per

page_text: cent Of manganese 01 to 20 per cent and of silicon 01 to 5 per cent ordinary
pig metal or any of the equivalents hereinbefore enumerated may be used instead
of the costly qualities of iron. hitherto deemed requisite and that when so used and
treated the resulting product is a steel of very superior quality possessing certain
marked characteristics of excellence. I have also discovered that when the
ingredients are as above mentioned, and are treated as above described the
presence of sulphur or phosphorus in the pig or other iron or other material
or materials under treatment to a degree which would materially injure ordinary
steel will be found not to injure my improved product.
There is however a practical difficulty in the production of an alloy or mixture
of chromium manganese and silicon arising from the fact that in the process of
refining and decarbonising metal the chromium manganese and silicon present are
oxidised It follows that in the open hearth, puddling, Bessemer and other kindred
processes although a large per centage of chromium manganese and silicon may at
the outset be present in the charge of iron under treatment or be added thereto
before the carbon has been to a great extent eliminated, or be added thereto
previous to the process of reduction refinement or decarbonisation such per centage
of chromium, manganese and silicon would be to a great extent oxidised and almost
entirely eliminated even after only a partial decarbonisation-It is therefore
manifest that if the chromium manganese and silicon additions were introduced
previously to or during the decarbonsing operation they would not remain in the
charge or be found present in the resulting product.
To obviate this I proceed as follows if pig metal cast iron scrap or a mixture of
these with steel or wrought iron scrap be used as the basis the metal is treated in
the ordinary way by the Bessemer, open hearth or other decarbonising and refining
process until the charge is decarbonised entirely or to a great extent-I then add
the per centages of chromium, manganese and silicon the amount of chromium,
manganese and silicon present in their respective alloys having been previously
ascertained so that the proportions of such alloys to be added may be regulated in
such a manner that the desired percentages of chromium manganese and silicon
respectively will be present in the resulting product at the close of the operation.
The percentages of chromium manganese and silicon are introduced as follows-
The chromium is introduced by preference by the use of chromium pig iron herein-
after referred to as the "chromium addition or any other alloy of chromium such
as ferro chromium which is incorporated with the charge either in a solid or melted
condition-The gross amount of chromium pig or ferro chromium to be added will
depend on the amount of chromium silicon and manganese which it contains and
also on the percentage of chromium silicon and manganese which the resulting
product is desired to contain.
.
"
I give the following illustration as an example I add to say two thousand pounds
of decarbonised iron six hundred and seventy two pounds of chromium pig iron
containing say from 8 to 10 per cent of chromium-Also if necessary there should
be added the quantity of ferro manganese or silicon spiegel meaning thereby a
compound of iron with silicon in excess that will give the required percentage of
manganese and silicon in the resulting product Where it is necessary to have
manganese present in a sufficient proportion to prevent red shortness and to
remove the slag and otherwise improve the steel if the chromium alloy does not
contain manganese or does not contain sufficient manganese such deficit must be
made gcod by the addition of a separate alloy such as ferro manganese in the usual
manner. It should be noted that it is requisite to have silicon present in sufficient
quantity as it enables injurious gases (such as those of sulphur or phosphorus or
hydrogen gas) to be removed from the materials under treatment and so produce
sound tee It follows therefore that where there is a deficit of silicon it should be
made good by adding a separate silicon alloy such as silicon pig or silicon cast iron-
Or the silicon and manganese may be added by means of one alloy containing both
silicon and manganese such as is commercially known by the name of "Ferro

page_text: manganese silicon" or any other suitable equivalent alloy-Or if desired the chromium
manganese and silicon may be added by means of one alloy containing manganese
chromium and silicon such as chrome silicon spiegel or any other suitable equivalent.
alloy When adding the manganese chromium and silicon alloys by means of one
or two alloys only in the manner just described it will be necessary to first ascer-
tain by analysis the amount of silicon and manganese or of chromium silicon and
manganese contained in such one or two alloys. so as to produce the desired effect
I prefer however to add each metal by means of separato alloys as a more reliable
result can thus be obtained-Such alloys may be added either in the solid or
molten condition.
It is very desirable to keep the carbon under 1.25 per cent in those steels
containing 15 per cent of chromium and upwards on account of the difficulty
which would be experienced in working the ingots if such percentage of carbon is
largely exceeded.
When it is desired that the material produced should have great toughness
combined with closeness of grain-I introduce such an amount of the chromium
manganese and silicon as will yield a steel having from 1.5 per cent to 2.5 per cent
of chromium '02 to 04 per cent of manganese and 02 to 04 per cent of silicon and
I increase the amount of chromium in varying proportions up to about 7 per cent
where greater hardness is requisite-As just mentioned where greater toughness is.
requisite I prefer to add the manganese and silicon in sufficient quantities so as to
produce in the resulting steel about 02 to 04 per cent of manganese and about .02
to 04 per cent of silicon.
The amount of manganese and likewise of silicon may be varied between the limits
indicated according to the purposes for which the steel is required thus where the
articles to be produced are of intricate form then either the manganese or the
silicon or both may be increased in order to produce greater freedom from honey-
combs the chromium also being varied according to the desired hardness as before
indicated After the chromium addition that is the alloy containing chromium
manganese and silicon or the separate alloys of each has or have been incorporated
with the charge it is ready to be run into moulds or other forms as may be
desired.
•
For special purposes when the material is not required to be turned or machined
I increase the proportion of manganese according to the particular quality desired
in the product.
If my improved steel is to be made by the crucible process the basis of the
operation or prime charge being wrought iron or steel scrap or both combined or
other suitable materials the process is then conducted in the usual way the amount
of carbon (if any is used) being preferably less than in the ordinary steel making
operations and the chromium addition that is the alloy containing chromium
manganese and silicon or the separate alloys of each is or are introduced into
the crucible at any stage of the process and so becomes or become thoroughly
incorporated with the charge.
This improved steely alloy or compound as made by me possesses both hardness
and toughness the degree of hardness depending as before stated on the amount of
chromium manganese and silicon it contains and it will be found to present an
extraordinary resistance to compression strains.
When it has been run into moulds that is to say when the molten material has
been used for producing "steel castings" in some cases I use it as cast that is in
its unannealed state but when special strength and toughness are required I anneal
such castings in the usual way provided that, and in such case provision should be
made that in the material annealed the per centage of manganese should not
exceed 2.25 per cent After such annealing the material will be found to possess a
peculiarly close grain of special density as well as toughness and hardness.
This material is specially adapted for a large variety of purposes such as car
wheels stamp castings, projectiles, and many other articles.

page_text: Having thus described my improved steel and the method of producing same
what I claim as my invention and desire to secure by Letters Patent is
1° As a new article of manufacture the production of a steely alloy or compound
from the ingredients and by the processes substantially as described.
.
2° The employment as ingredients in the manufacture from common qualities of 5
iron of a steely alloy such as is herein before described of chromium and manganese
and silicon respectively in the proportions above described.

page_text: 1, ROBERT HADFIELD of Sheffield in the County of York, Steel Manufacturer
do hereby declare the nature of this invantion to be as follows:-
This Invention has for its object the production and manufacture of a new steely
alloy or compound hereafter termed "Chrome Steel" the principal constituents
whereof are iron (ferrum) chromium-manganese and silicon.
. Such chrome steel combines most of the properties of ordinary carbon steel with
special excoilence and is of very high commercial value although comparatively
inexpensive to manufacture.
This economy in manufacture 1 effect by dispensing with the costly qualities of
iron heretofore employed for the production and manufacture of high class stoels-
When desired however such costly qualities of iron may be employed in conjunction
with my improved treatment.
The condition of the iron which forms the basis of my improved chrome steel
and from which it is manufactured may be that of ordinary pig metal cast iron,
steel, wrought iron, steel or iron scrap or a mixture of all or any of them, and the
process or processes by which the iron or steel is manufactured or reduced or
subsequently treated is immaterial the only necessary requirement being that the
iron before the addition of the chromium manganese and silicon should be sub-
stantially decarbonised by which I mean not necessarily devoid of carbon but that
the metal should be or should have been previously decarbonised wholly or to a
great extent-Hence my invention is applicable to the production and manufacture
of steel by means of the Bessemer, open hearth or other decarbonising and refining
processes or by means of the crucible processes; these processes being carried on in
the usual way as regards the Bessemer, open hearth, or kindred processes until the
metal under treatment is nearly or quite decarbonised when the requisite per
centages of chromium manganese and silicon are added while if the crucible process
be employed the chromium, manganese and silicon additions may be introduced at
any stage of the process.
The chromium, manganese and silicon are added thereto in suitable per centages
say for instance not less than three quarters of one per cent of chromium-one

page_text: tenth of one per cent of manganese-and a similar proportion of silicon―These per
centages vary in proportion however according to the resultant product desired to
be obtained.
The addition of the chromium manganese and silicon may be effected by any
suitable means.
My chrome steel may be hardened and tempered in the ordinary manner when
requisite.
It combines with peculiar hardness and closeness of grain an extraordinary
capability of resisting high strains of compression.
Dated 1
11002
SHIRLEY BOWDEN,
33, Southampton Buildings, Holborn, London,
Agent for the Applicant.

page_text: I ROBERT HADFIELD of Sheffield Yorkshire Steel Manufacturer do hereby
declare the nature of this 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 has for its object the production of a new steely alloy or com-
pound the principal constituents whereof are,-iron (ferrum) chromium, manganese
and silicon but which may also contain carbon as well as other ingredients such as
sulphur and phosphorus which may be present in the métal such alloy having most
of the qualities of ordinary carbon steel besides other qualities hereinafter mentioned
peculiar thereto-Such peculiar properties are chiefly derived from the presence of
certain percentages of chromium, manganese and silicon as hereinafter specified.
Such steely alloy or compound while possessing special excellence is comparatively
inexpensive to manufacture this economy arising from the fact that I dispense with
the costly qualities of iron heretofore employed for the production of high class
steels and employ instead all or any of the various substitutes presently mentioned-
I will now proceed to describe my invention and the means of carrying out the
same.
The condition of the iron which forms the basis of iny improved steely alloy or
compound and from which it is produced may be that of any ordinary pig metal or
cast iron (such as is generally made from mineral coal)-used in the manufacture
of steel, or wrought iron, steel or iron scrap or a mixture of all or any of these and
the process or processes by which the iron or steel is manufactured or reduced or
subsequently treated may be of the ordinary kind the only necessary requirement
being that the iron before the addition of the chromium manganese and silicon
should have been practically decarbonised by any well known process though as
regards crucible products it is not absolutely necessary to so decarbonise it.
My improved process is applicable to the manufacture of steel by means of the
Bessemer, open hearth or other decarbonising and refining processes or by means
of the crucible process these processes being carried on in the usual way-As
regards the Bessemer or open hearth or kindred processes they should be carried
on until the metal is nearly or quite decarbonised when the requisite per centages
of chromium manganese and silicon are to be added thereto as hereinafter directed-
If the crucible process be employed the chromium manganese and silicon may be
introduced at any stage of the process.
Hitherto in the manufacture of high class steels it has been considered necessary
or at all events most advantageous to employ the best and most costly qualities of
iron-Now I have discovered that if chromium together with manganese and
silicon are present in sufficient quantities say of chromium 75 per cent to 7 per

page_text: cent Of manganese 01 to 20 per cent and of silicon 01 to 5 per cent ordinary
pig metal or any of the equivalents hereinbefore enumerated may be used instead
of the costly qualities of iron hitherto deemed requisite and that when so used and
treated the resulting product is a steel of very superior quality possessing certain
marked characteristics of excellence. I have also discovered that when the
ingredients are as above mentioned, and are treated as above described the
presence of sulphur or phosphorus in the pig or other iron or other material
or materials under treatment to a degree which would materially injure ordinary
steel will be found not to injure my improved product.
There is however a practical difficulty in the production of an alloy or mixture
of chromium manganese and silicon arising from the fact that in the process of
refining and decarbonising metal the chromium manganese and silicon present are
oxidised It follows that in the open hearth, puddling, Bessemer and other kindred
processes although a large per centage of chromium manganese and silicon may at
the outset be present in the charge of iron under treatment or be added thereto
before the carbon has been to a great extent eliminated, or be added thereto
previous to the process of reduction refinement or decarbonisation such per centage
of chromium, manganese and silicon would be to a great extent oxidised and almost
entirely eliminated even after only a partial decarbonisation-lt is therefore
manifest that if the chromium manganese and silicon additions were introduced
previously to or during the decarbonsing operation they would not remain in the
charge or be found present in the resulting product.
To obviate this I proceed as follows if pig metal cast iron scrap or a mixture of
these with steel or wrought iron scrap be used as the basis the metal is treated in
the ordinary way by the Bessemer, open hearth or other decarbonising and refining
process until the charge is decarbonised entirely or to a great extent-1 then add
the per centages of chromium, manganese and silicon the amount of chromium,
manganese and silicon present in their respective alloys having been previously
ascertained so that the proportions of such alloys to be added may be regulated in
such a manner that the desired percentages of chromium manganese and silicon
respectively will be present in the resulting product at the close of the operation.
The percentages of chromium manganese and silicon are introduced as follows-
The chromium is introduced by preference by the use of chromium pig iron heroin-
after referred to as the "chromium addition " or any other alloy of chromium such
as ferro chromium which is incorporated with the charge either in a solid or melted
condition-The gross amount of chromium pig or ferro chromium to be added will
depend on the amount of chromium silicon and manganese which it contains and
also on the percentage of chromium silicon and manganese which the resulting
product is desired to contain.
I give the following illustration as an example I add to say two thousand pounds
of decarbonised iron six hundred and seventy two pounds of chromium pig iron
containing say from 8 to 10 per cent of chromium-Also if necessary there should
be added the quantity of ferro manganese or silicon spiegel meaning thereby a
compound of iron with silicon in excess that will give the required percentage of
manganese and silicon in the resulting product Where it is necessary to have
manganese present in a sufficient proportion to prevent red shortness and to
remove the slag and otherwise improve the steel if the chromium alloy does not
contain manganese or does not contain sufficient manganese such deficit must be
made good by the addition of a separate alloy such as ferro manganese in the usual
manner. It should be noted that it is requisite to have silicon present in sufficient
quantity as it enables injurious gases (such as those of sulphur or phosphorus or
hydrogen gas) to be removed from the materials under treatment and so produce
sound steel-It follows therefore that where there is a deficit of silicon it should be
made good by adding a separate silicon alloy such as silicon pig or silicon cast iron-
Or the silicon and manganese may be added by means of one alloy containing_both
silicon and manganese such as is commercially known by the name of
Ferro

page_text: manganese silicon "
or any other suitable equivalent alloy-Or if desired the chromium
manganese and silicon may be added by means of one alloy containing manganese
chromium and silicon such as chrome silicon spiegel or any other suitable equivalent
alloy-When adding the manganese chromium and silicon alloys by means of one
or two alloys only in the manner just described it will be necessary to first ascer-
tain by analysis the amount of silicon and manganese or of chromium silicon and
manganese contained in such one or two alloys so as to produce the desired effect
I prefer however to add each metal by means of separate alloys as a more reliable
result can thus be obtained-Such alloys may be added either in the solid or
molten condition.
It is very desirable to keep the carbon under 1.25 per cent in those steels
containing 1.5 per cent of chromium and upwards on account of the difficulty
which would be experienced in working the ingots if such percentage of carbon is
largely exceeded.
When it is desired that the material produced should have great toughness
combined with closeness of grain-I introduce such an amount of the chromium
manganese and silicon as will yield a steel having from 1.5 per cent to 2.5 per cent
of chromium 02 to 04 per cent of manganese and 02 to 04 per cent of silicon and
I increase the amount of chromium in varying proportions up to about 7 per cent
where greater hardness is requisite As just mentioned where greater toughness is
requisite I prefer to add the manganese and silicon in sufficient quantities so as to
produce in the resulting steel about 92 to 04 per cent of manganese and about .02
to 04 per cent of silicon.
The amount of manganese and likewise of silicon may be varied between the limits
indicated according to the purposes for which the steel is required thus where the
articles to be produced are of intricate form then either the manganese or the
silicon or both may be increased in order to produce greater freedom from honey-
combs the chromium also being varied according to the desired hardness as before
indicated After the chromium addition that is the alloy containing chromium
manganese and silicon or the separate alloys of each has or have been incorporated
with the charge it is ready to be run into moulds or other forms as may be
desired.
For special purposes when the material is not required to be turned or machined
I increase the proportion of manganese according to the particular quality desired
in the product.
If my improved steel is to be made by the crucible process the basis of the
operation or prime charge being wrought iron or steel scrap or both combined or
other suitable materials the process is then conducted in the usual way the amount
of carbon (if any is used) being preferably less than in the ordinary steel making
operations and the chromium addition that is the alloy containing chromium
manganese and silicon or the separate alloys of each is or are introduced into
the crucible at any stage of the process and so becomes or become thoroughly
incorporated with the charge.
This improved steely alloy or compound as made by Die possesses both hardness
and toughness the degree of hardness depending as before stated on the amount of
chromium manganese and silicon it contains and it will be found to present an
extraordinary resistance to compression strains.
When it has been run into moulds that is to say when the molten material has
been used for producing "steel castings" in some cases I use it as cast that is in
its unannealed state but when special strength and toughness are required I anneal
such castings in the usual way provided that, and in such case provision should be
made that in the material annealed the percentage of manganese should not
exceed 2.25 per cent After such annealing the material will be found to possess a
peculiarly close grain of special density as well as toughness and hardness.
This material is specially adapted for a large variety of purposes such as car
wheels stamp castings, projectiles, and many other articles.

page_text: Having thus described my improved steel and the method of producing same
what I claim as my invention and desire to secure by Letters Patent
1° As a new article of manufacture the production of a steely alloy or compound
from the ingredients and by the processes substantially as described.
2° The employment as ingredients in the manufacture from common qualities of 5
iron of a steely alloy such as is herein before described of chromium and manganese
and silicon respectively in the proportions above described.
Dated thin 19th dass of N
ambar 1000