BE887121A - PROCESS FOR THE FORMATION OF ZINC-ALUMINUM COATING - Google Patents

Description

       

  Process for the formation of zinc-aluminum coating.

  
The present invention relates to a process for the formation of zinc-aluminum coating on a substrate made of any material, but preferably steel sheets.

  
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molten metal, of suitable composition. The example that comes first to mind is dip galvanization, whether custom or continuous.

  
However, although those preceded by traditional galvanizing still provide effective protection against corrosion, it has become apparent that the use of coatings

  
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Even more marked and therefore even more effective layers of protective coatings are born.

  
Research developed in this direction has resulted in the appearance of new types of coatings, such as

  
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Subsequent studies had as their guiding idea

  
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corrosion in the most diverse environments.

  
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that * to ensure a quality coating, some of the coating alloys developed previously required very expensive preliminary surface treatment and therefore installations whose design and implementation were no less.

  
the above considerations explain the interest which the researchers take in obtaining a metallic coating bath by dipping, of a composition such as no special surface preparation and

  
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face or other faults.

  
This intention is part of these

  
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the invention are the result of work relating to it. the influence of. the addition of rare earth to well-known alloy baths.

  
 <EMI ID = 13.1> _The process which is the subject of the present invention is

  
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lique composed mainly of zinc and aluminum, but also containing a certain proportion of a rare earth alloy

  
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Among these particular metals. we can cite prin-

  
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count of impurities, or in the form of traces.

  
According to a first variant in the implementation

  
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Harbor. 3 to 15% by weight of aluminum.

  
A second method of applying the process

  
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aluminum * antimony and lead.

  
A third method of implementing the process of the invention consists in using a metal bath containing seat, aluminum, magnesium, lead and possibly copper.

  
A fourth modality of implementation of the pro-

  
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weight).

  
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next ximative (in% by weight)

  

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In yet another variant of the process of the invention

  
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following approximative: (on% by weight)

  

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A twelfth method of applying the

  
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A thirteenth method of implementing the process

  
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miachmetall and Ce-mischmetall in an amount such that the sum of their concentrations represents less than 0.01% by weight of the abovementioned bath.

  
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1. A method of forming a Zn-Al coating on a substrate made of any material, but preferably steel plates, characterized in that a metal bath is used, the majority of which is zinc and aluminum, but additionally containing a certain proportion of an alloy of rare earths and other metals, called mischmetall, higher proportion or

  
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Claims (1)

2. Method according to claim 1, characterized in that it consists in using a metal bath comprising from 3 to 15% by weight of aluminum. <EMI ID = 32.1> in that it consists in using a metal bath comprising zinc, aluminum, antimony and lead. 4. Method according to claim 1, characterized in that it consists in using a metal bath containing zinc. aluminum, magnesium, lead and possibly copper.  <EMI ID = 33.1>  <EMI ID = 34.1> 15% Al, 0.02 to O, 15% Sb, less than 0.02% Pb, balance in zinc and mischmetall. 6. Method according to claim 4, characterized in that it consists in using a metal bath containing 3  <EMI ID = 35.1>  <EMI ID = 36.1> , - tiller <EMI ID = 37.1> 8. Method according to one or more of the claims  <EMI ID = 38.1> deny having the following composition: (in% by weight),  <EMI ID = 39.1>  <EMI ID = 40.1> 9. Method according to one or more of claims 1 to 8, characterized in that it consists in adding simultaneously  <EMI ID = 41.1> molten metal bath. 10. Method according to one or more of the claims  <EMI ID = 42.1>  <EMI ID = 43.1> or Ce-miachmetall or La-mischmetall and Ce-miachmetall in an amount such that the sum of their concentrations represents less than O.Ol% by weight of the abovementioned bath.