US1425572A - Zirconium alloy and process of making same - Google Patents

Description

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FREDERICK 'M. BECKE'I, OF NIAGARA FALLS,

NEW YORK. ASSIGNOB TO ELECTRO METALLURGICAL COMPANY, OF NIAGARA FALLS, NEW YORK, A- CORPORATION OF NEST VIRGINIA.

ZIECONIUEK ALLOY AND PROCESS OF MAKING SAME.

No Drawing.

1 consisting essentially of zirconium, silicon and iron, and to a process of making the same.

It is well known that zirconia can be reduced by carbon in the electric furnace, but the resulting product is invariably contaminated by carbon, presumably chemically combined as zirconium in addition to being practically intusible, is only very slightly soluble in molten steel,

t and the same holds true of high-carbon ferrozirconium. Therefore the direct preparation by carbon reduction of ferrozirconium alloys suitable for use as additions to steel has not heretofore proven practicable.

I have discovered that silicon in sufiicient proportion possesses the property of excluding carbon from iron-zirconium alloys, and on the basis of this observation I am able to prepare directly by carbon reduction in the electric furnace,- iron-zirconium-silicon alloys which do not contain suflicient carbon to interfere to any material extent either with the electric furnace operation or with the subsequent employment ofthe alloy in the treatment of steel. Furthermore, the

silicon lowers the melting point of the alloy, and increases its solubility or its solution-rate in molten steel.

Following are specific examples in accordance with my invention, it being understood that the invention is not restricted to the particular proportions of charge compon'entsmentioned by way of illustration, since these will of course vary according to the specific composition of alloy desired. In all cases, however, the silicon will be in sufiicient proportion to the zirconium to exclude any objectionable proportion oi carbon from the product; and. in the preferred embodiment of the invention the proportion Specification of Letters Eatent.

carbid. This carbid, I

Patented Aug. 15, reaa.

application filed October 1, 19%. Serial No. 414,086.

of silicon will be at least'equal tothat of the zirconium.

Example 1.

The charge mixture contained in each 2,000 lbs.:

Silica rock. 710 lbs. Zirconia ore 550 lbs. Charcoal 660 lbs. Steel scrap 80 lbs.

The zirconia ore used contained:

. SiO 29.67 TiO 7 .05 ALB 1.64 F9 0.56

The alloy produced analyzed as follows;

Zr 30.33% Si 55.34 Fe 11.80 Ti 2.00 Al. 0.25

99.72% with traces only of carbon.

Ewample 2.

The charge mixture contained:

Silica rock 830 lbs. Zirconia ore 465 lbs. Charcoal 650 lbs. Steel scrap lbs.

The ore contained:

ZrO 76. 52% 8'10, 18.08 Fe O 2.58 TiO, 0.66 A1 0 1.34

The alloy produced contained: Zr 3 9.32% Si 4:268. Fe 16.54 Ti 0.46 C 0.04

i nium-carbid. Once this compound has been formed it becomes difficult to remove the and quite im it under ordinary conditions,

Alloys containing decidedly less zirconium than the foregoing are readily prepared in accordance With this process; but if it be attempted to exceed about 39.5% zirconium content in an alloy containing only 10% of iron, the operation is apt to become erratic, presumably due tothe formation of zircoproduct from the crucible, possible to tap Following is an example of the process as applied to alloys of relatively low zirconium content: I

The charge mixture contained:

Silica roclr e 1080 lbs. Zirconia ore 135 lbs. Charcoal 7 20 lbs.

By suitably varying the proportion of steel scrap or equivalent source of iron in the product, low carbon alloys are readily prepared ranging say from 10% or less up to 40% or more of zirconium-together with an equal or greater proportion of silicon, the balance principally iron.- It is of course to be understood that other elements, and particularly such as are normal components or impurities of ziroonia ores, as for example, titanium, may be present in the'alloy in minor proportions without departure from the invention, ,4

'carbid in interferin neonate My preferred carbonaceous agent is charcoal, although other carbonaceous materials such as coke or coal may be substituted therefor either Wholly or in part. 1

1 claim v 1. A low-carbon ferro-alloy consisting essentially of iron, silicon and zirconium, the silicon and zirconium each in excess of 10%.

2. Alloy according to claim 1 having a zirconium content of 10-40%, the silicon being present in at least as high proportion as the zirconium.

3. A low-carbon ferro-alloy consisting essentially of iron, silicon and zirconium, the silicon content materially exceeding the zirconium content.

4. Process of making a low-carbon .ferroalloy consisting essentially of iron, silicon and zirconium, comprising smelting in the electric furnace a charge comprising silica, a zirconium ore, a carbonaceous reducing agent, and a source oi? iron, the silica in 'suflicient proportion to prevent the formation of zirconium-carbiid in interfering quantities.

5. Process of making a low-carbon ferroalloy consisting essentially of iron, silicon and zirconium, comprising smelting in the I electric furnace a charge comprising silica, a ,ZII'COHIUII). ore, a carbonaceous reducing agent, and a source of'iron, the charge proportioned to yield an alloy containing silicon in at least as high proportion as the zirconium, whereby the formation of zirconium quantities is prevented.

6. Process of maliing a low-carbon ferroalloy consisting essentially of iron, silicon and zirconium, comprising smelting in the electric furnace a charge comp-rising silica, a zirconium ore,'a carbonaceous reducing agent, and a source of iron, the charge roportioned to yield an alloy containing silicon in material excessof the zirconium, whereby the formation of zirconium, carbid in interi'eringquantities is prevented.

In testimony whereof, I aflix my si nature.

4 FREDERICK M. BECliE'l.