Otto's Original - Quality products since 1901
Etching/Pickling/Burnishing

NIGRIT AI-Extra

Ethink ink, blackening agent and cold burnishing agent
• Liquid medium on acid basis
• Appearance: light blue-blue / clear
• For aluminium and aluminium alloys (reinforced with immediate effect)

Pictures may differ from the original.


Packaging units:
bottles with 100g, 250g and 500g
canister with 1000g
Application area: The solution supplied ready for use is to be filled into a resistant container made of GRP, HDPE or PP.
Appearance/smell: light blue-blue / clear
Appearance/Consistency: fluid
ph-value: acidic-based medium
Application: The solution supplied ready for use is to be filled into a resistant container made of GRP, HDPE or PP.
Degreasing and inserting the parts: The parts to be burnished must be degreased before cold burnishing. In the simplest case, this can be done by washing with alcohol.
Blackening effect: Thorough degreasing of the parts is a prerequisite for uniform blackening. Depending on the material, blackening occurs quickly (approx. 15-30 sec after application). If "NIGRIT AI-Extra " remains on the workpiece too long, loose oxides will accumulate on the surface, which must be removed after the process (expediently with a root brush or similar). If the blackening has not become sufficient, the burnishing process can be repeated after the material has been cleaned. - Here it has been found that more than two burnishing passes hardly show any significant improvement. If there is an irregular colouration after burnishing, this is an indication of insufficient degreasing.
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Burnishing is the process of creating certain oxide layers by chemical means. In many cases, steel parts must be protected from corrosion and should be given an attractive black colour. The dimensional accuracy of the parts is maintained and even highly polished surfaces retain their shine.

NEUTRASOL post-treatment
After removing the loose oxides, which should be expediently carried out in a neutralization bath with the product NEUTRASOL – Concentrate, Cat. No. 875, the workpiece should be dried and preserved.

Neutralization bath
Regular tap water together with our NEUTRASOL can be used to prepare the bath. The pH value must be checked constantly and should not fall below pH-10, otherwise the workpieces will start to rust.
Indicator paper is used for checking.

Preservation
EO post-treatment fluid, Cat. No.: 0871, is a temporarily effective, preservative metal protection for application after use of Nigrit AI-Extra. Corrosion is always undesirable, therefore the metal surface should be treated briefly with this fluid (thin application) after each use. The water-displacing additives reliably prevent contact between the metal surface and remaining moisture.

Other indications
No workpieces should be left in the burnishing bath or remain in it for too long, otherwise the burnishing agent will decompose and become unusable. When processing on a large scale, an exhaust system is required in any case, as combustible hydrogen gas can be formed by the decomposition of metal.

 

Questions about our products?
We will advise you by phone 06123 / 7046-0.