Improvements in the Manufacture of Alloys of Iron and Aluminium and Alloys of Steel and Aluminium.
Year: 1889

page_text: Date of Application, 12th Nov., 1889
Complete Specification Left, 5th Aug., 1890-Accepted, 27th Sept., 1890
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Alloys of Iron and Aluminium
and Alloys of Steel and Aluminium.
We SAMUEL PEARSON of George Street West Birmingham in the County of
Warwick Engineer and JAMES HENRY PRATT of No. 27 Bennett's Hill Birmingham
aforesaid Stock and Share Broker do hereby declare the nature of this invention
to be as follows:-
Our said invention has for its object the economical production of alloys of iron and
aluminium and alloys of steel and aluminium and consists of the process or combination
of processes hereinafter described for effecting that object.
We take ironstone or iron ore preferably of a kind containing a considerable
quantity of silicate of alumina or clay and mix therewith coke in the proportion in which
it is usually employed in the smelting of iron. We also add to the said mixture
of iron ore and coke fluoride of calcium or fluor spar in the proportion in which
limestone is usually added to ironstone and coke in the smelting of iron or the
manufacture of cast iron by the blast furnace. We charge the said mixture into
the blast furnace and ignite the coke and urge the furnace with a blast of hot or
cold air as in the ordinary method of manufacturing cast iron. The iron produced
is alloyed with aluminium. When an iron ore such for example as haematite or
peroxide of iron not containing clay is employed clay must be added to the ore
in addition to the materials we have enumerated.
Dither cast iron alloyed with aluminium or steel alloyed with aluminium may be
made in the blast furnace. When it is wished to make steel alloyed with aluminium
we employ the purest iron ores that is ores containing neither sulphur nor
phosphorus or containing one or both of those substances in a quantity insufficient
to affect the quality of the steel. We urge the blast furnace with a more copious
blast of air when we wish to produce steel than when we wish to produce iron in order
that the carbon in the cast iron first formed may be reduced by oxidation to the
proportion existing in steel. Or the cast iron may be melted in a cupola and a current
of air directed upon it as in the old process of refining iron. Or the steel may be
treated in a Besseiner converter. By either of the two last mentioned processes cast
iron alloyed with aluminium is converted into steel alloyed with aluminium.
Instead of wholly replacing the limestone commonly employed in smelting iron by
fluoride of calcium or fluor spar the limestone may be only in part replaced by fluor
spar. We have found in practice that by replacing twenty-five per cent. of the
limestone with fluor spar satisfactory results are obtained.
Dated this 12th day of November 1889.
W. T. WHITEMAN,
Agent for the Applicants.
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Alloys of Iron and Aluminium
and Alloys of Steel and Aluminium.
We SAMUEL PEARSON of George Street West, Birmingham in the County of
Warwick Engineer and JAMES HENRY PRATT of No. 27 Bennett's Hill Birmingham
aforesaid Stock and Share Broker do hereby declare the nature of our invention and
the manner in which the same is to be performed to be particularly described and
ascertained in and by the following statement :-
Our said invention has for its object the economical production of alloys of iron and

page_text: aluminium and alloys of steel and aluminium and consists of the process or combination
of processes hereinafter described for effecting that object.
We take calcined ironstone or iron ore preferably of a kind containing a considerable
quantity of silicate of alumina or clay and mix therewith in charging the blast furnace
coke in the proportion in which it is usually employed in the smelting of iron. We
also add to the said mixture of iron ore and coko fluoride of calcium or fluor spar in
the proportion in which limestone is usually added to ironstone and coke in the
smelting of iron or the manufacture of cast iron by the blast furnace. We charge the
said materials into the blast furnace and ignite the coke and urge the furnace with a
blast of hot or cold air as in the ordinary method of manufacturing cast iron. The
iron produced is alloyed with aluminium. When an iron ore such for example as
haematite or peroxide of iron, not containing clay, is employed clay must be added to
the ore in addition to the materials we have enumerated."
Either cast iron alloyed with aluminium or steel alloyed with aluminium may be
made in the blast furnace. When it is wished to make steel alloyed with aluminium
we employ the purest iron ores, that is, ores containing neither sulphur nor phosphorus
or only containing one or both of those substances in a quantity insufficient to affect
injuriously the quality of the steel made from them. We urge the blast furnace with
a more copious blast of air when we wish to produce steel than when we wish to
produce iron in order that the carbon in the cast iron first formed may be reduced by
oxidation to the proportion existing in steel. Or the cast iron may be melted in a
cupola and a current of air directed upon it as in the old process of refining iron. Or
the cast iron may be treated in a Bessemer converter and be practically deprived of
the whole of its carbon, the requisite quantity of carbon for the formation of steel
being reimported into the molten iron by the introduction of the requisite amount of
spiegeleisen or by the use of any of the well known methods resorted to for that
purpose. By either of the two last mentioned processes cast iron alloyed with
aluminium is converted into steel alloyed with aluminium.
Instead of wholly replacing the limestone commonly employed in smelting iron by
fluoride of calcium or fluor spar the limestone may be only in part replaced by fluor
spar. We have found in practice that by replacing twenty five per cent. of the
limestone with fluor spar satisfactory results are obtained.
In carrying our invention into effect we prefer to use Staffordshire iron ore or other
iron ore containing protoxide of iron and alumina and we find that the following
proportions answer well in practice namely:-40 cwts. of clay ironstone ; 11 cwts. of
limestone; 4 cwts. of fluor spar; about 60 cwts. of coal, when we employ hot blast,
or about 60 cwts. of coke when we employ cold blast. A mixture of coal and coke
may he used in either case with good effect.
The proportion of fluor spar indicated is the minimum quantity we prefer to employ.
The proportion of fluor spar to limestone may be increased and where the cost of fluor
spar is not prohibitory it may be employed exclusively that is it may wholly replace
the limestone.
When we employ iron ores not containing clay we add to the said ores clay in the
proportion of about one part by weight of clay to six or seven parts by weight of the
iron ore.
Although we prefer to employ the materials in the proportions given yet we do
not limit ourselves thereto as the proportions may be varied within considerable limits
with satisfactory results.
Having now particularly described and ascertained the nature of our invention and
the manner in which it is to be performed we declare that we claim as our invention
of "Improvements in the manufacture of alloys of iron and aluminium and alloys
of steel and aluminium ":-
First Manufacturing alloys of iron and aluminium by the process or processes
herein before described; that is to say, by the reduction of iron ores containing
alumina, fluoride of calcium or fluor spar being employed in the reducing process in
substitution wholly or in part of the limestone ordinarily emploved.

page_text: Secondly:-The modifications herein before described when haematite or peroxide
of iron ores are employed and the modification described when an alloy of steel and
aluminium is to be made.
Dated this Fifth day of Am1900
W. T. WHITEMAN,
Agent for the Applicants.