US1134127A - Crystalline ferrosilicon product and method of making the same. - Google Patents

Description

H. c. HARRISON. CRYSTALLINE FERROSILICON PRODUCT AND METHOD OF MAKING THE SAME.

APPLICATION FILED JULY30, I909- RENEWED SEPT. I, 1914.

1, 1 34,1 Q7 Patented Apr. 6, 191:5.

sA'r

s n re.

HERBERT CHAMPION HARRISON, OF LOCKPORT, NEW YORK, ASSIGNOR, BY MESNE ASSIGNMENTS, TO ELECTRO METALLURGICAL COMPANY, A CORPORATION OF WEST VIRGINIA;

CRYSTALIIINE FERROSILICON PRODUCT AND METHOD OF MAKING THE SAME.

Application filed July 30, 1909, Serial No. 510,477.

To all whom it may concern:

Be it known that I, HERBERT CHAMPION HARRISON, a subjectof the King of Great Britain, residing at Lockport, in the county of Niagara and State of New York, have invented certain new and useful Improvements in Crystalline Ferrosilicon Products and Methods of Making the Same; and I do hereby declare the following tobe a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to crystalline ferrosilicon products and methods of producing the same, and has for its object to produce such a product in a crystalline form which will correspond substantially to the formula Fe Si,, or to 54.2 per cent. silicon.

With these objects in view the invention consists in the novel method and product hereinafter more fully disclosed and particularly pointed out in the claims.

Referring to the drawing forming a part of this specification, in which the figure illustrates a conventional form of an electric furnace suitable for carrying out the process, and for producing the product: 1 represents suitable electrodes, 2 the furnace, 3 the charge, and 4 the molten product.

In carrying out the method, the ferrosilicon charge is so proportioned that there will be produced a ferro-silicon alloy containing as nearly as possible between 53 and 54.5 per cent. of silicon. The same is heated in the furnace in the usual way, is tapped out and cooled and then broken up, when throughout the product are found matrices filled with bright, shining, hard, brittle crystals in a plate form which analyze about 54.2 per cent. silicon, depending upon whether the particular matrix selected is relatively rich or poor in silicon. If the matrices. are melted and permitted to cool, these crystals invariably solidify first, which tends to show that they have a higher melting point than the ferro-silicon alloys on either side of the same. Crystals from the poorer matrices probably contain about .7 per cent. of impurities, while crystals from rich matrices analyze practically 54.2 per cent. silicon, corresponding to the formula Fe st taking the atomic weight of iron as 55.9, and of silicon as 28.4. These crystals are, of course, a

Specification of Letters Patent.

Patented Apr. 6, 1915.

Renewed September 1, 1914. Serial No. 859,721.

much purer compound of iron and silicon than the usual commercial alloys, and, therefore, they offer special advantages in metallurgy, over the regular alloys of say, 25 to 60 per cent. silicon. They contain less carbonand phosphorous than do such alloys, and hav ng a slightly higher melting point than the 1mpurer alloys they are less likely to lose their s1l1con during the process of purifying the metal. In other words, it is well recognlzed 1n metallurgy, that it is very important to obtain the purest product possible, and it is obvlous that a crystalline product of this nature 1s purer than the'chance alloys here tofore employed. It is also probable that when the silicon is liberated from a chemical compound, as is the case here, it being. in'a nascent state, so to speak, that it will be more active chemically in the molten iron than would be the case were it merely liberated from an alloy.

In many cases the crystals need not be separated from their matrices before being used, for the mixture consisting of the crystals and matrices can always be depended on to analyze substantially between 53 and 54.5 per cent. of silicon, which is a product sufiiciently pure for many purposes. If the charge is made up so as to produce other than 53 to 54.5 per cent. of silicon the crystal product becomes less, and it can be made to so widely differ from this silicon content that, the crystal product will disappear entlrely. In some cases the matrices on either side of the crystals are found to contain only about 51.28% of silicon.

What I claim is:

1. The method of producing crystalline IEBI'IO S1l1CO I1 corresponding to the formula Fe s WhICh consists in so chemically proportiomng a ferro-silicon furnace charge as to produce substantially between 53 and 54.5 per cent. of silicon; and in suitably producing ferro silicon from said charge in an electric furnace by maintaining the temperature at or above a predetermined critical temperature, substantially as described.

2. The method of producing crystalline ferro-silicon corresponding to the formula 'I e,Si,, which consists in "so chemically proportioning a ferro-silicon furnace charge as to produce substantially between 53 and 54.5 per cent. of silicon; in suitably producing ferro-silicon from said charge in an electric furnace by maintaining a constant temperature above a critical temperature; and in separating out the crystals thus formed, sub stantially as described.

3. The herein described ferro-silicon product consisting of matrices of ferro-silicon containing substantially between 53 and 54.5 per cent. of silicon and charged with ferrosilicon crystals corresponding to the formula 10 Fe Si substantially as escribed.

' 4. The hereindescribed ferro-silicon product consisting of bright, hard, brittle, plate like, crsytals corresponding to the formula Fe Si,; substantially as described.

In testimony whereof, I aflix my signature, in presence of two Witnesses.

HERBERT CHAMPION HARRISON. Witnesses:

W. R. CULMER, N. GOULD ALIEN

Images