Black Oxide Coating Problems

Only the inspector s pen is wavering.

Black oxide coating problems.

Where to get it done. To achieve maximal corrosion resistance the black oxide must be impregnated with oil or wax. Many more letters about black oxide and room temperature blackening can be found by searching the site. It is used to add mild corrosion resistance for appearance and to minimize light reflection.

563 south leonard street waterbury ct 06708 1 203 756 5521 1 203 756 9017 contact us online p o. Instead the black oxide coating is produced by a chemical reaction between the iron on the surface of the ferrous metal and the oxidizing salts present in the black oxide. Solving iron copper and zinc contamination problems. Aluminum and copper in ultra blak 400 baths or other black oxide solutions.

Box 790 waterbury ct 06720. A problem solving guide for black oxide coatings that s the direction this article is taking. Black oxide or blackening is a conversion coating for ferrous materials stainless steel copper and copper based alloys zinc powdered metals and silver solder. Control buildup of sludge red iron oxide zinc.

Achieving a cleaner deeper black finish. We use a high temperature black oxide to finish a number of different tools a couple of these tools have joints with a tight fit. Black oxide hi temp application. The reaction between the iron of the ferrous alloy and the hot oxide bath produces a magnitite fe3 o4 on the actual surface of the part.

Curtis you could confirm the source of the white residue by carefully scraping some of it off the parts and analyzing it. The finish should be oily black. Many jobshops offer black oxide services. The tools are thoroughly rinsed and soaked in hot water an extended period of time.

Black oxide is a conversion coating formed by a chemical reaction produced when parts are immersed in the alkaline aqueous salt solution operated at approximately 285 degrees f. The black oxide process is a chemical conversion coating. Putting a tick in that checkbox the coating should also be moderately corrosion resistant. As advantageous as this supplementary feature undoubtedly is black oxide failure does occur so we need to stay abreast of the common problems incurred by this oxidizing process.

Please go to our directory of jobshops and search for the term black oxide. If the residue is sodium or potassium salts it is likely that it came from the black oxide process. Avoiding excessive sludge and chemical buildup. Assessing process variables as with any high end engineering process numerous variables are at work during a black oxide coating sequence.

This means that the black oxide is not deposited on the surface of the substrate like nickel or zinc electroplating.