US1599869A - Process of manufacturing aluminum alloy - Google Patents

Description

Pairwise s2...- 1'4, 1926.

2mm nnn'rnzsnnm AND HENRY ma: moment, or mars, rnancn.

.rnocnss or man'urnc'runme nnumnum: ALLOY.

no mawm Application menrune 15,- 19:25,

The present invention has for its subject a new aluminum alloy of which the density is substantially equal to that of aluminum itself, but of which. the mechanical strength is -much higher than that of aluminum. This alloy ,is essentially characterized by the fact that its composition includes copper, manganese, iron and silicon em form of ferro-silicon, tungste magnesium, also cadmium, and aluminum, in suitable determined proportions ieldingi a metal which may be subjected 0 any mechanical treatment ,(such asv rolling, drawing, hammering, wire drawin and so forth, or even cast and which int is case gives products free from cracks and flaws.

The invention also relates to the process of manufacture of the said alloy, according to which process there is first prepare a rich alloy of the body above specified by fusion in a plumbago crucible lined with magnesia and containing a certain quantity of a mixture of wood charcoal, calcium fluoride, oxide of magnesium and arsen'eous acid, the rich alloy thus produced being after scouring, run into ingot moulds for subse quent incorporation in aluminum in the proportion (variable according to the uses for which the metal is adapted) of 10 to 15 parts by weight of rich alloy to .90 to 85 parts by weight of aluminum. S

Einally the invention has for its object a modification of the process, which'modification is more particularly applicable in the case of alloys adapted to be fused, and in which the magnesium and cadmium (this latter body may be replaced by sodium) are only inco' orated at the moment when the rich alloy is mixed with the aluminum, this inag'ne'sia and in the bottom of incorporation being made at a temperature at most equal to 725 C.

With reference to examples which are given solely as examples of the methods of car ing the invention into effect, be 'escribed the method of preparation of alloys suitable for various uses. In all cases the rich alloy is prepared by fusing the con stituents in a plumbago crucible lined with i which there are; first placed 25 grammes of the following --.mixture:

" x Grammes.

-Pulverized' beech charcoal 1000 Naturalcalciumfluoridenur 1000 yO'xidiofmagnesium; 250

Arseneous acid -=.1

loyed 1n the there will- 1 casting there are added,

Serial No. 37,573,.and in France May 11, 1925.

The crucible heated in a furnace permit- 7 ting of obtaining a regular and constant temperature (heavy'oil furnace or a furnace forheat vrecuperation ofthe Bigot system,

for example). When the fusion has been effected, the alloy time by means of a; rod of carbon from a retort lined with magnesia (a. rod of iron should never be used for this operation). Then from the surface of the mass in fusion The composition of the rich alloy thus pre- 60 is agitated for a very long pared varies according to the use to which the final alloy is adapted to be applied. Example I .-For obtaining an adapted to form plates, rods, tubes, wires, sections and so forth, the rich alloy is prepared from the following substances: copper, 40 grammes; manganese, 2 grammes; ferro; silicon, 5.35 grammes, having 55% iron and silicon (ice. iron 3.95 gms.) tungsten, 2 grammes; magnesium, 15 grammes; aluminum, 35.65 grammes. The quantity of rich alloy obtained by fusing the preceding substances, in the manner indicated above, is incorporated in 900 grammes of pure aluminum (i. e. 99 to 99.5% pu're).

Example I I .,-The rich alloy for the preparation of a meal adapted ture of castings of any nature, is obtained by fusing: copper, 42 grammes; manganese, 2 grammes; ferro-silicon, 5.35 grammes, having iron and silicon 45% gms. and silicon 2.40 gms); tungsten, 1 gramme; magnesium, 20 grammes; aluminum, 9.65 grammes.

is incorporate in 900 grammes of pure aluminum. According to one essential feature of the invention, in thisjcase particularly for the preparation of an alloy adapted for a ing the rich alloy to the aluminum, 20 amines of cadmium, this addition being or the purpose of eliminating cracks and flaws in the castings. y

The magnesium which enters into the formulae of the rich alloys which have been m- "dicated above (and also in the formula of the third example hereinafter set forth) may be added to the other constituents [of the gms, silicon 2.40

tfthe time of add-- alloy 7 for the manufaca The vquantit of rich alloy thus obtained 65 ,there is removed the mixture of powder and 1111111 mass.

In all cases it is advisable, before adding these additions, to purify the metal, as otherwise there is the risk that the magnesium is drawn into the slag. On the other hand it is essential to operate at a temperature which does not exceed 725 "C. The fusion of the pure aluminum, with the incorporation of the appropriate rich alloy, is preferably e'fi'ected in a plumbago crucible lined with magnesia and heated in an ordinary coke furnace.

The cadmium may be replaced by an equivalent quantity of sodium.

Example III.-A formula similar to the preceding is particularly suit-able for the manufacture of engine pistons copper, 52.50

' grammes; manganese, 5 grammes: ferro silicon, 5.50 grammes, having iron and silicon 45% (i. e. iron 3.03 gms, and silicon 2.47 gms.) tungsten, 1 gramme; magnesium, 20 grammes; aluminum, 46 grammes.

This quantity of ri'ch'alloy is incorporated in 850 grammes of pure aluminum with the addition, under the conditions specified above, of 20 grammes of cadmium. The 20 grammes of magnesium called for by the formula of the rich alloy may be added at the same moment as the. cadmium instead of being fused with the other constituents of the rich alloy.

Irrespective. of the forinula adopted, it is important, in order to obtain products of good quality and constant characteristics. to

use only pure metals and start with cu pros in the preparation of the rich alloys. The metal adapted to be rolled should be previously heated for one hour at a temperature between 400 and 450 C. After two or three rollings, the sheet should be re-heated under the same conditions, and this treatment is repeated until the required thickness is obtained. The'sheet istthen annealed at 450 0., and then immersed in a bath of hot water to which 5% of glycerine has been added. Annealing can then be effected at atemperature of 450 to 475 O., and then the plate is allowed to cool slowly in air.

The manufacture of tubes, wires, rods, sections, is effected in the same manner.

\ completed, it is advisable to'allow the metalto mature for from eight to ten days; and

subjecting them for one hour to annealing at a temperaure of 200 to 250 0-, which annealing is followed by immersion in a bath of boilingywater to which 5% of glycer- Once the mechanical treatment has been II and III)' can'be promoted by ine has been added. The same result is obtained by allowing -the 'furnace to cool after annealing for one hour.

The aluminum alloy in the form of castings obtained according to the invention can be readily tempered.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent is 1. A process for the manufacture of an aluminum alloy comprising fusing in a plumbago crucible lined with magnesia and containing a mixtureof wood charcoal, calcium fluoride, oxide of magnesium, and arseneous acid, a mixture of copper, manganese, ferro-silicon, tungsten, magnesium, and aluminum, so as' to roduce a rich alloy,

,scouring the rich a1 0y, running the rich alloy into ingot moulds, and subsequently mixing the rich alloy with pure aluminum.

2. A process for the manufacture of an al minum alloy comprising fusing in a plumbago crucible lined with magnesia and containing a mixture of wood charcoal, cal cium fluoride, oxide of magnesium, 'and arseneous acid, a mixture of copper, manganese ferro-silicon. tun sten ma esium and.

aluminum, so as to produce. a rich alloy, scouringthe rich alloy, running the rich alloy into ingot moulds, and subsequently mixing the rich alloy with pure aluminum, in .the proportion of 10 to 15 parts by weight of-rich alloy to 90 to 85 parts by weight of aluminum. r

3. A process for the production of an aluminum alloy for the production ofcastings comprising fusing copper, manganese, ferro-silicon, tungsten, magnesium, and aluminum, in a plumbago crucible lined with magnesia and containing a mixture of wood charcoal, calcium fluoride, oxide of magnesium, and arseneous acid, the rich alloy thus obtained being scoured, run into ingot moulds, and then mixed with aluminum and whilst mixing with the aluminum, adding magnesium and cadmium, this addition beloy thus obtainedbeing scoured, run into ingot moulds, and then mixed with aluminum, and whilst mixing with the aluminum, adding magnesium and sodium, this addition being made at' a temperature of about In witness whereof, we hereunto subscribe our riames this 3rd day of June, 1925.

- HENRY DE MONTBY. PIERRE BERTHELEMY