BE541259A

BE541259A -

Info

Publication number: BE541259A
Authority: BE
Priority date: 1955-09-09
Also published as: FR68197E

Description

       

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   Dans le brevet   prin@ipal n    536.560 du 16 mars 1955, on   décrit   un procedé pour laproduciton de revêtements ad- hérant à des aciers inoxydables,   o'est-à-dire   des alliages de fer avec du nickel et/ou du chrome, et à d'autres métaux   difficilement   attaquables,tels que le   nickel,le   chrome et leurs   alliages,de   préférence pour faciliter la déformation sans production de oopeaux,de ces métaux par laminage, étirage et analogue, ce procédé étant caractérisé par le fait que la surface de ces métaux,de préférence après un traitement dé- passivant, connu en soi, est traitée avec une solution acide, qui contient des ions manganèse, des ions oxalate et un composé oxygéné du soufre qui se décompose dans les conditions de tra- vail,

   avec séparation de l'acide sulfureux et du soufre,cette 

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 solution ayant un pH de   0,7 à   2,0,de préférence de 1,0 à 1,5 mais ne oontenant pas d'ions halogène. 



   Comme produit   d'acidification,en   vue de régler et de conserver la valeur du pH,on a préconisé dans le brevet principal l'usage d'acide   sulfurique,diacide   sulfaminque ou d'acide sulfureux. 



   On a découvert, toutefois. que l'usage d'acide nitrique   et/ou d'acide   phosphorique,comme produit.d'acidification, présente pour l'application pratique des avantages considé- rables par rapport aux acides proposés à cet effet dans le brevet principal pour la raison que l'accumulation des sulfa- tes complexes trouble le traitement aveo ces acides. 



   Ci-dessous on donne, à titre d'exemples,des solutions convenent à cet effet. 



  EXEMPLE I 
Carbonate de manganèse 12 g acide   nitrique ( à   69%) 24 cm3 acide oxalique 15 g thiosulfate de sodium 5 g eau pour faire un litre   @     TEMPLE   II carbonate de manganèse 15 g acide oxalique 12 g acide phosphorique (à 75%) 12 g thiosulfate de sodium 5 g eau pour faire un litre 
A part cela, le procédé correspond à celui indiqué dans le brevet principal.



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   In main patent no.536,560 of March 16, 1955, a process is described for the production of coatings adhering to stainless steels, i.e. alloys of iron with nickel and / or chromium, and other metals which are difficult to attack, such as nickel, chromium and their alloys, preferably to facilitate the deformation without production of chips, of these metals by rolling, drawing and the like, this process being characterized in that the surface of these metals, preferably after a passivating treatment, known per se, is treated with an acid solution, which contains manganese ions, oxalate ions and an oxygenated sulfur compound which decomposes under working conditions,

   with separation of sulfurous acid and sulfur, this

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 solution having a pH of 0.7 to 2.0, preferably 1.0 to 1.5 but not containing halogen ions.



   As an acidification product, with a view to regulating and maintaining the pH value, the main patent advocated the use of sulfuric acid, sulphaminic acid or sulfurous acid.



   We found out, however. that the use of nitric acid and / or phosphoric acid, as an acidification product, has for practical application considerable advantages over the acids proposed for this purpose in the main patent for the reason that the accumulation of complex sulfates disturbs the treatment with these acids.



   Below are given, by way of example, suitable solutions for this purpose.



  EXAMPLE I
Manganese carbonate 12 g nitric acid (69%) 24 cm3 oxalic acid 15 g sodium thiosulfate 5 g water to make a liter @ TEMPLE II manganese carbonate 15 g oxalic acid 12 g phosphoric acid (75%) 12 g thiosulfate sodium 5 g water to make a liter
Apart from that, the process corresponds to that indicated in the main patent.

Claims

ABSTRACT The object of the invention is a process for the production of coatings adhering to stainless steel and to other diffiolably etchable metals, such as niokel, chromium and their alloys, preferably with a view to facilitating deformation. , without chip formation, of these metals by rolling, drawing and the like, according to main patent no.536.560 of March 16, 1955, the present process being characterized by the fact that for the acidification nitric acid is used and / or phosphoric acid in place of the acids cited in the main patent.

The invention relates more particularly to certain modes of application, as well as certain embodiments, of said method; and it is more particularly still, and this titled new industrial products kes metals treated by this process, the special elements and devices suitable for its implementation as well as articles and objects manufactured using @ these metals.