Year: 1885

page_text: I, ROBERT HADFIELD, of Hecla Works, Newhall Road, Attercliffe, Sheffield,
Steel Manufacturer, do hereby declare the nature of this invention to be as
follows:-
This Invention relates to improvements in the manufacture of steel and other
projectiles and has for its object to obviate the difficulties hitherto experienced in
combining the requisite degree of hardness with toughness in such projectiles.
It is well known that in such articles it is necessary to have one part extremely
hard and the other part soft or tough.
.
To effect this I first cast or forge that part of the article which is required to
be hard and form therein suitable dovetailed grooves or slots or their equivalents-
I then cast the softer portion of the article on to the hinder part and run the fluid
metal employed in the manufacture of such softer portion into such dovetailed
grooves or slots or their equivalents thus firmly uniting the two portions together
and combining with such perfect union the advantage of preserving the original
properties of extreme hardness and great toughness required in the respective
portions as hereinbefore mentioned.
SHIRLEY BOWDEN,
Agent for the Applicant.

page_text: I ROBERT HADFIELD of Attercliffe, near Sheffield in the County of York, 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 relates to improvements in the manufacture of steel and other
projectiles and has for its object to obviate the difficulties hitherto experienced in
combining the requisite degree of hardness with toughness in such projectiles.
It is well known that it is necessary to have the head and point of a projectile
extremely hard and the body and base thereof softer and tougher-To meet these
requirements particularly in the case of forged or cast steel projectiles hardening
and tempering processes have to be employed which processes cause detrimental
internal strains to be set up between the harder and softer portions of the projectile
thus frequently causing it to fly in pieces, on impact and so preventing it from
doing its work.
Now in order to obviate these disadvantages I make the projectile in two distinct
and separate parts each part being of a different temper and quality-By this
means I am enabled to make the head and point of the projectile of any desired
degree of hardness and the body and base thereof of any requisite degree of
softness and toughness without producing the detrimental internal strains and
.results before referred to.
In order to carry out my invention I either cast or forge the head of the projectile
and form therein suitable taper or other dovetailed grooves slots or serrations or
their equivalents.
When the head is cast such grooves, slots, serrations or their equivalents are
formed therein at the time of casting but when the head is forged they are cut
out or otherwise formed therein after it is made.
I may also cast or otherwise form in or on such head one or more projecting
shank or shanks-I then place .such head in a suitable mould and cast the body
and base of the projectile thereon by running molten steel or iron or other metal
or material of any suitable temper or quality into the dovetailed grooves, slots or
'serrations or their equivalents so formed in the head of the projectile as aforesaid
thus firmly connecting and fastening the two parts together-When one or more
shank or shanks are likewise cast in or formed upon the head as before mentioned
they serve still further to hold the two parts together.
I would here remark that an essential feature of my invention consists in making
such two parts at two different and distinct operations so as to allow the harder
portion constituting the head and point of the projectile to thoroughly set before
casting the body and base thereon-I thus prevent the harder portion becoming
mixed with the softer material which would result in rendering both parts useless-
If desired the base may have a suitable core formed therein for the bursting
charge.
.
Preferably I slightly heat the head of the projectile before placing it in the
mould in order to prevent injury thereto arising from its too sudden expansion

page_text: when pouring the molten metal or material thereon and therein to form the body
and base as already described.
When the head of the projectile is made of forged or cast steel it may be
hardened or tempered either in its forged or cast state or annealed and then
hardened-Or such head may be made of chilled cast iron or of any other suitable
metal or material.
By my invention as hereinbefore described I produce a compound projectile built
up of two separate and distinct qualities of metal or material so connected as to
have the advantage of preserving intact their respective qualities of great hardness
and extreme toughness I thus effectually obviate the great difficulty and dis-
advantage hitherto experienced in the manufacture of steel and other projectiles as
I firmly connect and fasten together the head and base of the projectile without
causing the metals or materials whereof they are composed to become mixed
whereby I avoid producing a rotten and worthless compound-At the same time
I greatly economise the cost and labor of manufacture.
Figure 1 of the accompanying drawings shews a longitudinal section of the
head of a projectile having dovetailed grooves or slots a formed therein in the
manner herein before described.
Figure 2 shews the head of a projectile having a shank b cast thereon in addition
to such dovetailed grooves or slots a.
Figure 3 is a longitudinal sectional view shewing the two parts of a projectile
connected and fastened together according to my invention A being the harder
portion forming the head and point and B the softer portion forming the body and
base of the projectile.
Figure 4 shews an external view of a projectile made according to my invention
the dotted lines Cindicating the line of junction between the two parts A and B.
Figure 5 is a plan taken on the lines D E Figures 2 and 3.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is
1° Making a steel or other projectile in two parts at two separate and distinct
operations each part being made of a different and distinct quality of metal or
material and subsequently connecting and fastening such parts together all
substantially in the manner and for the purposes hereinbefore described and
shewn.
2° Forming suitable taper or other dovetailed grooves or slots or serrations or
their equivalents and likewise if desired one or more suitable shank or shanks in
or on the head of a projectile all substantially in the manner and for the purposes
herein before described and shewn.