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Electrochemical treatment

Elektropol-R is the first company in Poland to have used the unique process of internal electropolishing of acid-resistant pipes.

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Technology

 

ETCHING

 

Object before (left image) and after etching.

It's immanent to steel processing to introduce impurities into surface of detail. Grease, residuals of grinding and polishing compositions, oxidation, inclusions of pure iron or other metals efficiently prevent natural built-up of protecting passivation layer what opens door to corrosion. Mechanical cleaning is usually unsuccessful and in case of complex shapes is difficult or expensive or risky due to possible damage of detail. In practice, electrochemical etching was proven to be the most efficient and cost effective way of cleaning surface of steel details from corrosion promoting impurities. Moreover, electrochemical etching improves the look of the surface, smoothes sharp edges, removes colour stains from welds or cuts and appropriately prepares the surface for next steps of the processing chain like passivation or electropolishing.

 

 

PASSIVATION

 

Results of passivation after etching.

 

Results of passivation after electroppolishing.

Quite frequently the default level of steel corrosion resistance is too low for given usage. Spontaneously created firm barrier layer of oxides protecting against steel corrosion is very thin and vulnerable to mechanical damage. In case of unfavourable conditions like high moisture or contact with saltwater or other aggresive media there is a good risk of protection layer damage and consequently - corrosion. Electrochemical passivation is economically efficient and exceptionally effective method of improving natural corrosion resistance of metals. It is possible to increase the thickness of steel protection layer tenfold and provide its appropriate hardness and firmness. Such a protection layer is an excellent barrier against most common environmental corrosion factors. Electrochemical passivation has no impact on shape of processed detail - only its surface proprieties are modified in a positive manner.



 

 

 

 

 

 

ELECTROPOLISHING

 

Besides galvanisation (plating), electropolishing is undoubtly the most advanced technique of electrochemical processing of metals. The main purpose of electropolishing is fine smoothing of the detail's surface but in practice this goes together with deep anodal passivation resulting in excellent corrosion resistance of steel. In case of chromium-nickel steel alloys, electropolishing treatment has additional positive effect: concentation of chromium on the surface layer increases significantly (iron and nickel are being etched with a faster rate), so the surface becomes much harder. 

Object before process -> Object after etching, ready for electropolishing -> Object after electropolishing


Electropolishing is a very fine process - etching is only limited to these fragments of the surface what are elevated above the average in a microscopic scale while macroscopic structure remains completly unaffected. Consequently, all fine details and contours remain unaltered while the surface gains aesthetic glossy look. Such a surface provides very easy cleaning what is essential for food, pharmaceutical or electronical industry for instance. Because actual hardness of steel has no impact on the process of electropolishing, the cost of electropolishing treatment does not depend on surface hardness reached on preceding steps of the processing chain - unlikely to traditional mechanical methods of steel polishing. The chemical composition of media used for electropolishing and appropriate control of physicochemical parameters of the process are critical for its efficiency and final results. No wonder, know-how is a secret and fundamental asset for companies involved in electropolishing besides machinery and people. Exceptional experience, proprietary know-how, skilfull engineering and high motivation stand behind ELEKTROPOL-R. You may trust the quality of our service!