US1196767A

US1196767A - Method of changing the composition of iron and steel.

Info

Publication number: US1196767A
Application number: US81463714A
Authority: US
Inventors: Bruce Ford
Original assignee: Individual
Current assignee: Individual
Priority date: 1914-01-27
Filing date: 1914-01-27
Publication date: 1916-09-05
Anticipated expiration: 1933-09-05

Description

' FORD.

METHOD OF CHANGIN COMPOSITION OF IRON AND STEEL.

PPL AT L D AN A [C 1 ,1 96,767. Patented Sept. 5, 1916.

ml BruceffibraL I zzw awz Q BRUCE FORD, 0F PHILADELPHIA, PENNSYLVANIA.

METHOD OF CHANGING THE COMPOSITION OF IRON AND STEEL.

Specification of Letters Patent.

Application filed January-27, 1914. Serial No. 814,637.

To all whom it may concern:

Be it known that I, BRUCE FORD, a c1t1- zen of the United States, and a residentof Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented a certain new and useful Method of Changing the Composition of Iron and Steel, of which the following is a specification.

The principal object of the present invention is to provide for quickly, economically and uniformly changing the composition of objects of iron and steel to a substantial depth and to avoid waste of the medium.

In accordance with the present invention the composition of an iron or steel object is changed by submerging it ina suitably heated medium and limiting the heat of the medium to a temperature a little below its temperature of decomposition and locally decomposing a portion of the medium in the vicinity of the object by raising the temperature of the object above the temperature of decomposition of the medium by electric resistance heating and permitting the object to rapidly absorb the medium as it is decomposed in contact therewith.

The invention further comprises the improvements to be presently described and finally claimed.

Reference will be made to the accompanying drawings in which is illustrated princi-- pally in section one form of apparatus by means of which the process can be practised. In practising the process in connection with the apparatus shown in the drawings.

the medium 1 is contained in a suitable receptacle 2 and is heated by combustion in the furnace or chamber 3. v

3 is a diagrammatic representation of a burner such as may be employed for burning oil.

4, is a cover for the receptacle and 5 a ventilating hood that-may be employed, if desired. 6 and 7 areelectrodes properly insulated as at 8 and arranged to depend into the medium 1. These electrodes are connected in the circuit 9 which may be the ,is heated by this electric resistance heating? secondary circuit an appropriate transformer. The object, 10, of iron or steel to be treated is immersed in the medium 1 and connected into the, circuit of thdelectrodes so as to be heated 'byresistance The object to a temperature higher than the temperatureof decomposition of the medium so that the medium is decomposed in the vicinity of the object and in contact with it and the medium is therefore rapidly absorbed by the object, so that the composition of the object is quickly changed, While at the same time there is no waste of the medium since it is not decomposed otherwise than locally as above described.

The cross-sectional area of the ends of the object may be reduced as shown at 11, thereby increasing the electrical resistance of the circuit at or near the contacts to provide heat to compensate for heat conducted away by the contacts or

electrodes

6 and 7, Furthermore the ends of the electrodes are so shaped that the object may be sprung in between them thus facilitating the introduction and removal of the'object. The cover 4, of course, can be removed for this pur-' pose. While one object is shown and one set of contacts for each end of the object is shown, it is evident that the electrodes may be provided with a number of separate contacts arranged side by side and if necessary black and bone black and the like, or a mixture of these or some of them; or the medium may contain manganese or silicon in some appropriate form or in fact any of these substances which are available in the treatment of iron and steel.

For the sake of further explanation it may be stated that the current will vary. However, by way of example, it may be said that for each square inch of the cross-section of the metal to be treated there is required approximately two thousand to ten thousand 'amperes and for each foot in length' of the metal to be treated there is required from Patented Sept. 5, 1916.

two to five volts, according to the. shape of i the cross-section and the capacity. of the mefdium for taking away heat, buii'fin any event oinpo'sition'aiid' the fact tli, he medium ,is-otli'erwise heated to a temperature below its point of decomposition 1s.,product1ve of economy in operation and results.

In using the word quickly in describing the time required for the substantiai conversion of the composition of the metal re;

erence is had to time measured in minutes or hours as distinguished from hours and days and even weeks,

@bviously modifications may be made without departing from the spirit of the invention which is not limited in matters of detail or otherwise than as the prior state of the art may require or as the claims may indicate.

What I claim is:

1. The process of changing the composition of an iron or steel object which consists in heating a suitable medium from a source of heat other than the resistance electric heating hereinafter referred to and limiting its heat to a temperature below its temperature of decomposition, immersing the object in such medium and locally decomposing the portion of the medium in the vicinity of the object by raising the temperature of the latter above the temperature of the medium and above the temperature of decomposition of the medium by resistance electric heating, and permitting the object to rapidly absorb the medium as it is decomposed in contact therewith.

2. The process of changing the composition of iron and steel objects which consists in heating a suitable medium from a source of heating other than the resistance electric seer/er heating hereinafter referred to are in. its heat to a less temperature tha 1 its perature of decomposition, us a objec in such medium, reducin QI@SF- sectional area of the ends of the object, rai"- ing the temperature of the medium in vicinity er the object above the ten aer of decomposition of the medium by passa current through the object and its reduc ends, and permitting the object to ahsoi the medium as it is decomposed in cen therewith.

8. The process of changing the composition of an iron or steel object which consists in heating the object while in contact with a suitable medium from a source or heat' other than the resistance electric heatmg hereinafter referred to and limiting its heat to a temperature below its temperature of decomposition, and locally decomposing the portion of the medium in the vicinity of the object by raising the temperature of the latter above the temperature of the medium and above the temperature of decomposition of the medium'by resistance electric heating and permitting the object to rapidly absorb the medium as it is decomposed in contact therewith.

BRUCE FURD.

Witnesses:

C IFFORD K. CAssEL, FRANK E. FRENCH.