US1966481A - Homogeneous antimony-bismuth alloy - Google Patents

Description

Patented July 17, 1934 PATENT OFFICE 1,966,481 nomoosusous An'rmomr-msnm'm ALLOY, A

' Pierre Berthelemy, Henry de Montby,

aris, France,

Marie, Pouvreau,

Socit Anonyme iran Brevets Berthelemy de No Drawing.

Serial Application No. 657,262. In France October 29, 1929 and Jean- II to caise dite: Montby, Paris, France 2 Claim (CL 15-1) Messrs. Berthelemy and de Montby have shown that it is possible to incorporate homogeneously a metal such as cadmium into, aluminium and aluminium alloys, by using magnesium as 1!) vehicle tor cadmium. This procedure brings about a perfectly homogeneous incorporation in well defined proportions, whereas it cadmium is introd 'ced direct into the alloy, a heterogeneous incorporation results which makes it impossible to obtain with certainty a determined proportion oi cadmium.

generally a metal is homogeneously distributed in other metals when such metal forms a solid solution or a combination with these latter metals.

The researches oi- Messrs. Berthelemy, de Montby and Pouvreau have led them to discover incorporate homoinium alloys other metals which corporated heterogeneously, by using as a vehicle a metal capable of forming a solid solution or a combination with the metal to be incorporated,

the latter having an amnity with aluminium.

Thus, lead, for instance, which while forming neither solid solutions nor compounds with aluminium, does form a solid solution with magnesium which in turn forms a solidv solution with aluminium.

The object of this invention is to apply in industry this general method of incorporation into aluminium and aluminium alloys of an element which otherwise cannot be distributed homo geneously.

According the alloy in to this invention, after preparing the usual way and introducing its various ingredients, one adds a binary alloy consisting of the metal to be incorporated and that which is used as a vehicle.

As examples, the following binary alloys may. be cited: antimony-bismuth, lead-magnesium etc.

The incorporation, however, can be carried out not only by using a binary alloy but also by consecutive or simultaneous incorporation of the additional metal and the metal used as a vehicle. It the antimony and bismuth are not added to the aluminium in the form ota-binary alloy, they should be added either simultaneously or in such rapid succession as to form in eii'ect a binary alloy, so that the antimony and the hismuth simultaneously act to cause them to be incorporated in the aluminium alloy, in the form of a solid solution: v It is to be clearly understood that the use of the method of this invention does not exclude the addition of magnesiumto the alloy, in cases where magnesium is no longer used as a vehicle for the metal to be incorporated The following are examples of alloy formulas 00 prepared according to the invention:

Formula No. 1

- Grammes Silic. aluminium 25 c5 Magnesium 9 Antimony 10 Bismuth 5 Aluminium"... 951

, Formula No 2 g Grammes Silic. a1uminium- 25 Magnesium 9 Bismuth 10 Antimony 5 Aluminium 951 Formula No 3 Grammes Bilic. aluminium 25 Magnesium 9 Lead 20 Aluminium 946 If bismuth is added to alumin um a hetero geneous mixture is found however it the bismuth is simultaneously added with antimony to the aluminium, as in the form of a binary alloy, the joint action and bismuth causes them out the aluminium in the tion, so that the antimony and the bismuth are homogeneously distributed throughout the alloy.

Experiments have shown that bismuth is not miscible in aluminium save in very small proportions, as for example about 0.3%. By util- 10o izing the antimony, a large proportion of hismuth can be homogeneously distributed in the final alloy. By reason of this uniform distribution, the applicant prevents the formation of electro-chemical couples, and

this is highly deproduce corrosion. Since the bismuth is distributed in the alloy in a proportion which is much greater than the normal limit of about 0.3% due to the action of the antimony, the" bismuth is retained in the final alloy in the free state. tains, therefore, its essential characteristics, so

physical action This is contrary to vious inventors, in

upon the final alloy. the proposals made by prehich it was suggested to antimony to the aluminium, in order to protect the aluminium against the action of salt water.

Prior inventors sought to add the antimony to aluminium in order to produce a surface formation of antimony oxychloride on the piece of aluminium.

Applicants restrain or of aluminium alloy by means which are essentially physical, in 'contradistinction to the chemical means previously utilized.

This application is a continuation in part of our application Ser. No. 488,987, filed in the U. S. Patent Ofice on October 15, 1936.

What we claim is:

prevent the corrosion i. A method of forming an aluminium alloy containing a major proportion of aluminium and also containing antimony and bismuth, which so that the alloy takes up bismuth in excess of 0.3%, in the form PIERRE BER HELEMY. HENRY nn MONTBY.

J EAN MARIE POUVREAU.

substantially si-