US1477922A - Treating magnesium and alloys comprising the same - Google Patents

Description

Patented Dec. 118, 19

ETE S tartan I PATENT @FIFHCE.

EMIL WOLLNER, OF SCHWANHEIM-ON-THE-MAIN, AND FELK THOMAS, OF FRANK- FORT-ON-THE-MAIN, GERMANY, ASSIGNORS TO THE FIRM: CHEMISCHE FABRIK GBIESHEIM-ELEKTRON, F FRANKFORT-ON-THE-MAIN, GERMANY.

TREATING MAGNESIUM AND. ALLOYS COMPRISING THE SAME.

1T0 Drawing.

To all whom it may concern:

Be it known that we, EMIL VVoLLNnR and FELIX THOMAS, citizens of Germany, residing at Schwanheim-on-the-Main, Germany,

5 and Frankfort-on-the-Main, Germany, re-

spectively, have invented certain new and useful Improvements in Treating ,Magnesium and\Alloys Comprising Same, of which the following is a specification.

Our invention refers to the treatment of magnesium and alloys containing it with a view to protecting the metal against atmospheric influences. As is well-known to those skilled in the art, metallic magnesium as well as most magnesium alloys are subject to oxidation and do not resist the influence of the atmosphere. In view of these circumstances an efiective protective coating is of vital importance for their technical applicability. Of the metal varnishes commonly used, a very few only can be employed for magnesium and magnesium alloys inasmuch as the varnish solvents mostly in use and in many cases even the varnishes them selves will after a longer or shorter period and in most cases in cooperation with the moisture of the air react with the metal,

thus causing the varnish coating to get d'ull and ultimately to get destroyed.

The production of a more or less thick coating of pure magnesium hydroxide or magnesium oxide as proposed in the German patent specification No. 347781, does not "offer a suflicient protection, for such a 95 coating is not permanently resistive against atmospheric influences owing to the hydroxide or the oxide absorbing carbonic acid from the air and losing its original resistivity and impermeability while increasing in volume. Moreover its insulating capacity in the case of magnesium alloys is inferior to that shown with pure magnesium for the reason that the foreign metals remain in the oxid coating in a finely subdivided state. Finally in the case of magnesium alloys the coating appears to be more porous than with pure metallic magnesium.

We have found that a layerof oleate or resinate of magnesium which is preferably f produced directly upon the metal, for in-' stance by a protracted treating of the parts to be coated in an oil-water-soap-emulsion or in some other suitable manner, forms a protective coating of high chemical resis- Application filed May 25, 1922. Serial No. 563,718.

tivity and possessing excellent mechanical qualities. Such a coating is unaffected by the air as it will not absorb the carbonic acid contained therein. On account of its greasy nature which may be due to the fact that small quantities of oil or resin are mechanically retained in the layer, it does not take on any water, is considerably more elastic than an ordinary oxid coating, possesses great hardness and resistivity against mechanical wear and is capable of being highly polished.

The polishing of the coated parts, whereby a very beautiful, non-metallic lustre is imparted to them, takes place either during the formation of the layer of oleate or resinate by allowing the process to take place in a polishing barrel and if necessary with the addition of a suitable polishing means, or subsequently in a well known manner.

In order to produce coloured coatings, suitable dyes may be added either during the production of the coating, whereby a colouring extending throughout the entire coating is obtained, or subsequently by means of coloured varnishes.

In order to produce on magnesium or an alloy comprising it a protective coating such as above described, we may for instance heat the metal in an emulsionized mixture of about 2 parts by weight of soap, 3 parts linseed oil and 100 parts water. The layer of oleate formed on the metal will vary in thickness, according to the duration of the treatment, from about one hundredth of a millimetre to one millimetre and above that. It substantially consists of magnesium oxide, magnesium oleate and oil in excess. Coatings of oleate or resinate on magnesium or a magnesium'alloy impart to the metal the appearance of enamel, horn, or the like according to the colour and polish chosen, and therefore make these metals suitable for an extensive application in the manufacture of artificial horn, buttons and the like. In addition thereto the coatings renders these metals adapted for technical purposes also in cases where they could not be employed without it, as in consequence of moisture or the like a too rapid oxidation of the unprotected metal would occur.

We wish it to be understood that we do not desire to be limited to the exact substances and roportions given, for many obvious modi cations will occur to a person skilled in the art.

We claim:

1. The method of rendering metal containing magnesium resistive against atmosspheric influences, consisting in forming on the metal a protective layer of a magnesium salt of an acid capable of forming a soap.

2. The method of rendering metal containing magnesium resistive against atmosheric influences, consisting in forming on t e metal a protective layer of magnesium 'oleate.

3. The method of rendering metal con- 'taining magnesium resistive against atmospheric influences, consisting in treating the metal with a substance capable of forming thereon a protective layer of a magnesium salt of anacid capable of forming a soap.

4. The method of rendering metal containing magnesium resistive against atmos-- pheric influences, consisting in treating the metal witha substance capable .of convertin the skin of said metal into a magnesium sa t of an acid capable of forming a soap.

5. The method of rendering metal containing magnesium resistive against atmospheric influences, consisting in treating the metal with a substance capable of converting the skin of said metal into magnesium oleate. I

6. The methodof rendering metal con taining magnesium resistive against atmospheric influences, consisting in treating the metal with an emulsionized mixture of soap, oil'and Water.

7. The method of rendering metal containing magnesium resistive against atmospheric influences, consisting in treating the metal with an emulsionized mixture of 2 parts soap, 3 parts linseed oil and 100 parts water.

8. The method of rendering metal containing magnesium resistive against atmospheric influences, consisting in forming on the metal a coloured layer of a magnesium salt of an acid capable of forming a soap.

9. The method of rendering metal containing magnesium resistive against atmospheric influences, consisting in forming on the metal a protective layer of a magnesium salt of an acid capable of forming a soap and polishing said layer.

10. As a new article of manufacture, partly worked metal containing magnesium, said metal 'being provided with a protective layer of a magnesium salt of an acid capable of forming ,a soap.

11. As a new article of manufacture, sheet metal containing magnesium, said sheet metal being provlded with a protective layer of a magnesium salt of an acid capable of forming a soap.

12. As a new article of manufacture, sheet magnesium provided with a protective layer of a magnesium salt of an acid capable of forming a soap.

13. As a new article of manufacture, partly. worked metal Y containing magnesium, said metal being provided with a protective layer of magnesium oleate.

14. As anew article of manufacture, a metallic shape containing magnesium, said shape being provided with a protective layer of a magnesium salt of an acid capable'of forming a soap. 1

In testimony whereof we atfix our signatures.-

FELIX THOMAS, EMIL WOLLNER.