Improvements in the Manufacture or Production of Metal Plates Hardened at One Side.
Year: 1891

page_text: Date of Application, 3rd Jan., 1891
Complete Specification Left, 5th Oct., 1891-Accepted, 7th Nov., 1891
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture or Production of Metal Plates
Hardened at One Side.
I, ALBERT SAILLER, of Witkowitz, Moravia, in the Empire of Austria, Chief
Engineer do hereby declare the nature of this invention to be as follows:-
This invention has for object the manufacture or production from molten
homogeneous iron or mild steel (hereinafter referred to as metal) of plates, blocks
or massés (hereinafter referred to as plates) hardened at one side. This hardening
of one side of the plate is effected by bringing the upper portion or surface of
the metal whilst in a molten state within a suitable vessel and after the lower
portion thereof has become solidified or has commenced to solidify, into contact
with a hardening agent that combines or unites with; or dissolves in, the molten
metal. As hardening agents, there may be employed suitable carbonaceous
substances such as charcoal, graphite, and coke; pig iron; spiegeleisen; ferro-silicon
or other known hardening agents.
The relative thicknesses of the hardened and unhardened portions of a plate
produced according to this invention will vary according to the nature of the
article to be produced and the purpose for which it is to be used. The desired
relative thicknesses of the two portions of the plate can be obtained according to
my invention by a suitable choice of the material employed for the side walls and
In many
the bottom of the vessel in which the hardening process is carried out.
cases it will be advantageous to cool the bottom artificially, in order to effect a
quicker solidification of the lower portion of the metal.
According to one way of carrying out this invention the molten metal is run
into a vessel of rectangular form in cross section and after the lower portion of
the metal has solidified or has commenced to solidify, the upper molten portion is
gradually and uniformly covered over its entire surface with a pulverized solid
hardening agent, until it begins to solidify, or until the desired degree of hardness
has been produced.
After the hardening due to the taking up of the active constituents of the
agent employed, has penetrated to the desired depth, the metal is either allowed
to cool naturally, or the cooling process is quickened by pouring water upon the
metal, or by placing an iron cover upon it.
The vessel usually employed will be an iron frame, a mould box, or an ingot
mould. In order to prèvent the molten metal from cooling too quickly through
the 'side walls, whereby the metal forming the upper and outer portions of the
metal bath would be solidified too soon and would consequently not be hardened
or would not be sufficiently hardened, the side walls, when the top surface is small,
are lined internally with material that is a bad conductor of heat, as for examples
fire proof stones, or fire clay. For large castings the vessel 'need not be lined.
The bottom of the vessel may advantageously be made of cast iron, and when
thick plates are to be produced, or when the molten metal fills the vessel to a
considerable height, it should be provided with a special cooling device, in order
that the lower portion of the metal can be caused to solidify quicker than the
upper portion or surface so that it shall remain in its soft or unhardened but tough
state. Whether the bottom of the vessel should be of cast iron with or without
means for cooling it or whether it should be of material that is a bad conductor
of heat will depend on the nature of the plate or other object to be produced and
the depth to which it is to be hardened.

page_text: Care must be taken that the molten metal is poured into the vessel at the
proper temperature and that it is in a tranquil state in the mould, that is to say,
that there is no violent generation of gas therein when the hardening agent is
applied.
A plate produced in the manner described will be very tough if the metal when
poured into the vessel or mould has this property, notwithstanding that the metal
at one side may be very hard.
The hardening of the upper portion of the plate can be effected to such a degree
that it is converted into cast iron, without affecting the lower portion.
A plate whose hardened side has been combined in the manner described with
sufficient carbon to convert it into hard steel, but not into cast iron, can be
hammered, rolled, and bent without difficulty whilst hot, and can thus be brought
to any desired form and thickness.
In
Instead of applying the hardening agent in a pulverized form to the metal
surface to be hardened, the molten metal may be covered with a hardening
substance in a fluid state and of less specific gravity than the molten metal.
this manner the hardening agent can be brought quietly and uniformly into contact
with the upper molten portion of the metal to be hardened, whereby not a welding,
but a cementing or intimate and uniform mingling of the two is effected at the
surface.
A vessel suitable for carrying out this process, comprises a vessel lined with a
substance that is a bad conductor of heat and in which are formed at opposite
sides, gates or passages for introducing the molten metal and hardening agent
respectively, the outlet of the gate or passage for the hardening agent, terminating
at a suitable distance above that for the molten metal.
The hardening agent for examples pig iron, or spiegeleisen in a molten state, is
allowed to flow through the one gate or passage onto the surface of the molten
metal to be hardened when the surface of this metal, which is introduced into the
vessel through the other gate or passage, has risen up to the level of the lower
end of the first mentioned gate or passage. By this means the hardening metal
and the metal to be hardened are brought quietly and uniformly together at their
contact surfaces.
It is obvious that two or more gates may be used instead of one for introducing
the hardening agent and molten metal. By suitably cooling the bottom part of the
vessel the plate to be produced can have imparted to it exactly that degree and
depth of hardness which is best suited for the purpose for which the plate is to
be used.
As will be obvious the process hereinbefore described is different from the
known process of hardening molten homogeneous iron or mild steel from a converter
or open hearth furnace, by means of coal dust. In the latter process the object is
to effect a carburation as uniform as possible throughout the entire mass of metal
and can only be effected by treating the metal to be hardened, prior to or during
the passage of the steel into the mould, whereas my process has for its object to
harden the metal at one side and must be carried on in the mould itself, after the
molten metal has been poured therein.
Dated this 3rd dov of January 1801
A. SAILLER,
By L. W., per F. B.

page_text: COMPLETE SPECIFICATION.
Improvements in the Manufacture or Production of Metal Plates
Hardened at One Side.
I, ALBERT SAILLER, of Witkowitz, Moravia, in the Empire of Austria, Chief
Engineer, 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 object the manufacture or production from molten
homogeneous iron or mild steel (hereinafter referred to as metal) of plates, blocks or
masses (hereinafter referred to as plates) hardened at one side. The hardening of
one side of the plate is effected by bringing the upper portion or surface of the metal,
whilst in a molten state within a suitable vessel and after the lower portion thereof
has become solidified or has commenced to solidify, into contact with a hardening
agent that will combine or unite with, or dissolve in the molten metal.
hardening agents, there may be employed suitable carbonaceous substances such as
charcoal, graphite, and coke; pig iron, spiegeleisen, ferro-silicon or other known
hardening agents.
As
The relative thicknesses of the hardened and unhardened portions of a plate
produced according to this invention will vary according to the nature of the
article to be produced and the purpose for which it is to be used. The desired
relative thicknesses of the two portions of the plate can be obtained according to
my invention by a suitable choice of the material employed for the side walls and
the bottom of the vessel in which the hardening process is carried out.
In many
cases it will be advantageous to cool the bottom of the vessel artificially in order
to effect a quicker solidification of the lower portion of the metal.
In the accompanying drawings,
Fig. 1 is a vertical section illustrating one way of carrying out this invention
according to which the molten metal is run into a vessel a of rectangular form in cross
section, and, after the lower portion e of the metal has solidified or has commenced
to solidify, the upper molten portion d is gradually and uniformly covered over its
entire surface with a pulverised solid hardening agent e until it begins to solidify,
or until the desired degree of hardness has been produced.
After the hardening due to the taking-up of the active constituents of the agent
employed, has penetrated to the desired depth, the metal is either allowed to cool
naturally, or the cooling process is quickened by pouring water upon the metal, or
by placing an iron cover upon it.
The vessel a usually employed will be an iron frame, a mould box, or an ingot
mould. In order to prevent the molten metal from cooling too quickly through the
side walls, whereby the metal forming the upper and outer portions of the metal
bath would be solidified too soon and would consequently not be hardened or would
not be sufficiently hardened, the side walls, when the top surface is small, are lined
internally with material a' that is a bad conductor of heat, as for examples, ganister
or fire clay. For large castings the vessel need not be lined. The bottom b of the
vessel may advantageously be made of cast iron, and when thick plates are to be
produced, or when the molten metal fills the vessel to a considerable height, it
should be provided with means whereby it can be rapidly cooled, or be made hollow
for the circulation therethrough of a cooling fluid, in order that the lower portion
of the metal may be caused to solidify quicker than the upper portion or surface
and remain in its soft or unhardened but tough state. Whether the bottom of the
vessel be of cast iron, with or without means for cooling it, or whether it be of
material that is a bad conductor of heat, will depend on the nature of the plate or
other object to be produced, and the depth to which it is to be hardened.
Care must be taken that the molten metal is poured into the vessel or mould at
the proper temperature, and that it is in a tranquil state in such vessel or mould,

page_text: that is to say, that there is no violent generation of gas therein, when the hardening
agent is applied.
A plate produced in the manner described will be very tough if the metal poured
into the vessel or mould has this property, notwithstanding that the metal at one
side may be very hard.
The hardening of the upper portions of the plate can be effected to such a degree
that it is converted into cast iron, without affecting the lower portion.
A plate whose hardened side has been combined in the manner described with
sufficient carbon to convert it into hard steel, but not into cast iron, can be
hammered, rolled, and bent whilst hot, and can thus be brought to any desired form
and thickness.
Instead of applying the hardening agent in a pulverized form to the metal surface
to be hardened as herein before described, the molten metal may be covered with a
hardening substance in a fluid state and of less specific gravity than the molten metal.
In this manner the hardening agent can be brought quietly and uniformly into
contact with the upper molten portion of the metal to be hardened, whereby not a
welding, but a cementing or intimate and uniform mingling of the two is effected
at or near the surface.
A vessel suitable for carrying out this process is illustrated in vertical section in
Fig. 2 and comprises an outer metal frame or casing a lined with a substance a¹ that
is a bad conductor of heat and in which are formed at opposite sides, gates or
passages g and e for introducing the molten metal and hardening agent respectively,
the outlet e for the hardening agent, terminating at a suitable distance above the
opening g' for the molten metal.
The hardening agent c, for examples pig iron, or spiegeleisen in a molten state, is
allowed to flow through the gate or passage e onto the surface of the molten metalf
to be hardened when the surface of this metal, which is introduced into the vessel
through the other gate or passage g, has risen up to the level of the lower end of
the gate or passage e, the lower portion of this metal having solidified or being in
the act of solidifying. By this means the hardening metal and the metal to be
hardened, are brought quietly and uniformly together at their contact surfaces.
It is obvious that two or more gates may be used instead of one for introducing
both the hardening agent and the molten metal. By suitably cooling the bottom
part of the vessel, the plate to be produced can have imparted to it exactly that
degree and depth of hardness which is best suited for the purpose for which the
plate is to be used.
As will be obvious the process herein before described is different from the known
process of hardening molten homogeneous iron or mild steel from a converter or
open hearth furnace by means of coal dust. In the latter process the object is
to effect a carburation as uniform as possible throughout the entire mass of metal
and can only be effected by treating the metal to be hardened, prior to or during
its passage into the mould, whereas my process has for its object to harden the metal
at one side only, and must be carried on in the mould itself, after the molten metal
bas been poured therein.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what
I claim is :-
1. The manufacture or production from molten iron or molten soft steel, of plates
hardened at one side by bringing a suitable carboniferous substance, as for examples
charcoal, graphite, coke, pig iron, spiegeleisen, ferro-silicon or other suitable
hardening agent, either in the form of powder, or in a fluid state, into contact with
the upper surface or portion of the molten metal after the lower portion of the
metal has become solidified or has commenced to solidify substantially as herein-
before described.
2. Effecting the hardening treatment referred to in the preceding claim, in a
vessel the inner side of which is made of material that is a bad conductor of heat,

page_text: as for example ganister or fire-clay, for the purpose of preventing the metal forming
the upper and outer portions of the metal bath becoming solidified too quickly and
thus losing its capacity for taking up the active constituents of the hardening agent
as set forth.
3. In the manufacture or production of plates hardened at one side according to
Claim 1, artificially cooling the bottom of the vessel in which the hardening is
effected, for the purpose of accelerating the solidification of the metal at the side
opposite to that to be hardened as set forth.
Dated this 5th day of October 1891.
A. SAILLER,
Per L. W., by J. E. S.