US90075A - Improved process of hardemjwg steel - Google Patents

Description

Toallwhom'itma/yconcem:

Be it'known that I,- HENRY BROOKE, of Pittsburg, in the county of Allegheny, and State ofPennsylvauia,

HENRYABRDO-KE. or; Prr'rsBnRc, PENNSYLVANIA.

' Letters Patent No. 90,075, dated Ma 13,1869.

" .mrnovnn PROCESS or meme- 3mm,

T e Schedule referred to'in these Letters Patent-and making part of the same.

have invented certain new and useful Improvements in l r Hardening Steel andI do hereby declare that the following is a' full, clear, and exact description thereof.

The nature of my invention consists in a process of making and hardening what is known as semisteel,

or homogeneous castings, and is adapted to the following articlesof manufacture, viz, rollers of all descrip tions; shear-blades, circular. and other; cutters, machineknives, cannon-shot, plow-mould boards, and engravers plates. v i

To enable others skilled in the art to use my invention, I will" describe the process, first, as adapted to linear articles, suchas plow mould-boards or engravcrs plates.

Ordinary bar-iron is cut to any suitable length, and

. deposited, with the ordinary fluxes, in an ordinary melting-pot, or crucible, and is subjected to the heat arising from any ordinary melting,or air-furnace.

When the metal acquires a fluid state, an ordinary iron mould is provided, of the size and shape requisite for the required casting. A plate of ordinary iron, and

of the shape of the back ofthe required casting, is

- placed in the mould, in scuba manner, that when the molten metal is poured into the mpuld, it will flow up 1 against said metalplate, to which it-lvill adhere;

When the casting becomes cold,:it is taken from the mould, and its outer surfaces made true and free from imperfections, by theaid of any suitable machinery.

It is thenftaken and deposited in an ordinary carbonizing, or.,c0nverting-furnace, where it'is subjected to the heat thereof. i

. Having remained in'the furnace snificient time, said i 1 periodof time being regulated by the degree of hardness the casting is calculated to. have, it is taken out,

p and the iron plate removed from the same, and all its? surfaces will be carbonized, and will have the degree of hardness cast-steel possesses, save the surface which. was against the iron plate, whichfiiotbein'g subjected to the carbonizing-process, in consequence of the iron plate intervening, possesses the nature and tensile strength ofi ordinary wrought-iron. V 1

1 In casting and hardening cylindrical articles, such as rollers, the method employed of meltingbar-iron is the same as before described. Moulds are furnished, of octagonal or hexagonal shape, and the fluid metal poured therein. g

Whensolidified,'the casting is'taken to an ordinary steam-hammer, by whose aid it is made as nearly cylindiical as possible. It is then taken to the'ordinary carbonizing, or converting-furnace, and carbonized to whatever degree of hardness is required, leavin'g'the inner portion of the same wrought-iron, whilst the outer surface has become steel.

The advantages arising from the use of my invention are, that semi-steel, or homogeneous castings, when hardened, possess greater virtues than cast-steel does,

since steel is very liable to fracture by any sudden jar, or disarrangement of machinery, especially when it is very hard.

Rbllers, when constructed wholly of steel, are made of greater diameter, in consequence of this fact, than if they were made of WIOHghlrlI'OH; but, as the outer surfaces of wrought-iron rollers are not of suflicient hard ness to withstand the pressure of the metals passmg through them, they areinadmissible.

Rollers made by my process, as herein described,

possessjtwo natures and qualities, viz, that of wroughtiron in the main body, and'steel at their peripheries,

being, as it were,.steel rollers with wrought-iron cores. Such rollers can be made of smaller diameter, not only saving metal, but also drawing out the required metal more uniformly than rollers of larger diameters.

As shear-blades have been heretofore constructed, they have been made of wrought-iron, with a steelpiece welded thereto, requiring considerable skilled labor to perform the same, and the blades are also liable to accident, as the weld is oftentimes defective. By the use of my described process,-such articles are .made solid, but are hard at the required point.

Cannon-shot, when constructed in like manner, will withstand a heavier'concussion. The point, being carbonized, will penetrate, whilst the base, being homog'eneous, will not sufier molecular deterioration.

Having thus described the nature and use of my invention,

What I claim as new, and desire to secure by Letters Patent, is-- The process of making and hardening homogeneous castings, substantially as herein described,.when applied tothe articles enumerated herein. 7

In testimony that I claim the foregoing as mytg wn, I affix my signature, in presence of two witnesses.

T p 7 HENRY BROOKE.

rWitnesses: I

. PERGEVAL Bncunrr,

B. M. Onneo.