Go to GlobalSpec.com Home
Free Registration 
Download Engineering Toolbar
GlobalSpec Home
Find:      Advanced Search >>
Product Announcements: chromium oxide
Elite Metal Finishing Services, Inc. - Passivation
Elite Metal Finishing Services, Inc.
Passivation

In basic terms, passivation is a combination of cleaning and the creation of a protective layer. The protective layer results from removal of contamination that is left on the surface of stainless steel after manufacturing. Contamination can lead to a shortened component life. The transparent oxide film created during passivation protects the stainless steel from corrosion.

More >>
Passivation

Passivation is a chemical process that removes iron compounds and contaminants from stainless steel surfaces that are presented during manufacturing, machining and welding of stainless steel products including stainless steel processing systems installations. Controlled passivation alters the surface composition of stainless steel without significantly affecting the stainless steel and creates an anodic oxide/hydroxide film that is 10 to 50 Angstroms thick. The result is a high chromium oxide surface and removal of contaminants, both of which are essential to the longevity of the passive layer and reduction of corrosion.

In basic terms, passivation is a combination of cleaning and the creation of a protective layer. The protective layer results from removal of contamination that is left on the surface of stainless steel after manufacturing. Contamination can lead to a shortened component life. The transparent oxide film created during passivation protects the stainless steel from selective oxidation (corrosion).

At Elite a variety of part shapes and sizes can be passivated, including:

  • Pharmaceutical Processing Equipment
  • Clean-room Equipment
  • Filters
  • Gas Delivery Systems
  • Gears
  • Hardware
  • Heat Exchangers
  • Investment Castings
  • Medical Implants
  • Pumps
  • Pressure Vessels
  • Springs
  • Stampings
  • Tanks
  • Tubing & Pipe
  • Vacuum Chambers
  • Valves & Fittings
  • Water Purification Systems
  • Surgical Instruments
IMT North America, Inc. - Thin-film coating
IMT North America, Inc.
Thin-film coating

Thin-film coating technology

Thin-film coatings, which are later structured, are applied by means of physical vapour deposition (PVD) processes. These coatings are generated by two processes:
• sputter etching (cathodic arc deposition)
• vapour deposition

More >>
Thin-film coating

Thin-film coating technology

Thin-film coatings, which are later structured, are applied by means of physical vapour deposition (PVD) processes. These coatings are generated by two processes:
• sputter etching (cathodic arc deposition)
• vapour deposition

We coat and structure the following wide range of materials in serial production:
Metal coatings:
• chrome
• anti-reflex chrome (chromium oxide)
• aluminium
• gold
• titanium
• platinum
• rhodium
• other coatings on request

Dielectric coatings:
• optical anti-reflection (simple and broadband anti-reflection)
• SiO2
• other coatings on request

For the coating process, we use the latest, process-controlled systems from leading manufacturers

Central Electropolishing Co., Inc. - Pickling of Stainless Steel
Central Electropolishing Co., Inc.
Pickling of Stainless Steel

Pickle Passivation of Stainless Steel. Pickling is the removal of any type of high temperature related scale such as heat treatment or weld burn. Wherever stainless steel has been heated by welding, heat treating or any other means to the point where a multi colored oxide layer can be seen on the su...

More >>
Pickling of Stainless Steel

Pickle Passivation of Stainless Steel. Pickling is the removal of any type of high temperature related scale such as heat treatment or weld burn. Wherever stainless steel has been heated by welding, heat treating or any other means to the point where a multi colored oxide layer can be seen on the surface of the stainless, there is a chromium depleted layer on the surface of the stainless steel below the oxide layer. The lower chromium content of course gives lower corrosion resistance. Pickle Passivation is the answer to restore the best corrosion resistive performance. In order to do this the damaged metal layer must be removed, exposing the fully alloyed stainless surface.If you choose to mechanically remove this layer it may leave abrasives or other foreign particles imbedded in the surface of the stainless material. Chemical removal is the best solution to this problem. Central Electropolishing can help you decide the best means of removal of this infective discoloration, whether it be employing a Nitric Acid Bath or use of a specially formulated pickling paste. The bottom line is we are ready and able to help you with this unsightly potentially corrosive situation.

Allegheny Surface Technology - Electropolishing Services
Allegheny Surface Technology
Electropolishing Services

Electropolishing is an electrochemical process that removes surface metal by attacking the high points on the surface. The surface becomes smoother and any contaminants and free irons will be removed. This will improve the corrosion resistance, reduce the product adhesion and contamination buildup, deburr and create a lustrous finish.

More >>
Electropolishing Services

Allegheny Surface Technology has been electropolishing for more than a decade. We maintain multiple operation lines containing different electrolytic solutions. We also have developed reliable methods to perform electropolishing without submerging your work piece into a tank. This enables us to electropolish large work pieces and to perform our service On-Site. We do have the necessary electrolytic solutions available to handle the common grades of stainless steel. Allegheny Surface Technology employs experienced and highly skilled craftsmen who have the necessary training and experience to perform electropolishing.

Advantages of Electropolishing

Polishing- Electropolishing decreases the surface roughness without creating directional lines and creates a lustrous surface. Corrosion resistance will be improved by removing contaminants introduced to the surface during the manufacturing process and handling of the part. Electropolishing also leaves a nickel-chromium enriched surface layer that enhances the metallic properties of stainless allowing the oxide layer to form.

Ease of Cleaning- By attacking the high points, electropolishing levels the surface of the material; thereby reducing product adhesion and contamination build up. Therefore, cleaning can be performed more efficiently and effectively.

Electropolishing has been proven to reduce bacterial bio-film build up, appearance of rouging.

De-burring- Electropolishing is well suited for de-burring. The electropolishing process naturally has greater current densities at high points and less at low points. Due to the higher current densities at the high points the material and burrs, dissolve at a much faster rate, leading to a smooth clean surface.

Aesthetics- Through proper electropolishing the microscopic surface become smooth and clean, containing a nickel-chromium enriched surface that results in a lustrous finish. This allows a visual inspection to be completed since imperfections will be magnified.

Electropolishing is performed by submerging your work piece into a temperature controlled electrolytic bath. Your work piece is connected to the positive end of a rectifier supplying DC at low voltage and high current. The negative terminal of the rectifier is connected to specially designed cathodes to ensure proper current flow through the electrolytic bath. The design and placement of the cathodes, the design of the rack holding your work piece and the number of contact points on the work piece are critical to ensure a uniform finish.

Applying electric current to the setup will start the electropolishing process. The longer the current is applied the more material will be removed until all high points have been eliminated. Extending the electropolishing process may reveal pores and orange peel, which is an indicator for material defects and reveals the internal structure of the metal. At Allegheny Surface Technology we try to avoid this impact by documenting our processes per application. Our quality control department assures the repeatability of our performance. Our stringent final inspection guarantees that all customer requirements are met.

Ogden Manufacturing Co. - Tubular Heaters
Ogden Manufacturing Co.
Tubular Heaters

The most versatile of all electric heating elements, the tubular heater is capable of being formed into virtually any configuration. The basic design consists of a helical coil of nickel-chromium resistance wire precisely centered in a metal sheath. This coil is surrounded by magnesium oxide powder which is vibration loaded to insure even density throughout the length of the heater.

More >>
Tubular Heaters

The most versatile of all electric heating elements, the tubular heater is capable of being formed into virtually any configuration. The basic design consists of a helical coil of nickel-chromium resistance wire precisely centered in a metal sheath. This coil is surrounded by magnesium oxide powder which is vibration loaded to insure even density throughout the length of the heater. This entire assembly is then reduced to the finished diameter, compacting the MgO and "freezing" the coil in the center of the heater. The range of ratings, sizes, materials and terminations available makes the tubular heater adaptable to many industrial, commercial and scientific applications.

  • Copper Sheath: Water heating, water solutions non-corrosive to copper.
  • Steel Sheath: Immersion in oils, molten salt baths, alkaline cleaning solutions, tars and asphalt. Also suitable for clamping to metal surfaces and casting into aluminum.
  • Stainless Steel Sheath: Corrosive liquids, food processing equipment.
  • Incoloy Sheath: Air heating, radiant heating, cleaning and degreasing solutions, plating and pickling solutions, corrosive liquids.

Other sheath materials are also available for application considerations. Commonly specified are 316 stainless steel and Carpenter 20 stainless steel for corrosive immersion heating, copper clad steel for metal casting, Inconel for high temperature applications, and titanium for severely corrosive solution heating. Porcelain and ceramic coatings can also be provided for corrosive atmospheres in process air applications, immersion heating, or for other application considerations.

Please click on the links to the right for more information.

Allegheny Surface Technology - Pickling/Chemical Cleaning Services
Allegheny Surface Technology
Pickling/Chemical Cleaning Services

Allegheny Surface Technology offers In-House and On-Site Pickling / Passivation services. We can pickle passivate inside or outside a tank, depending on the size of your product. Pickling is the removal of oxide layers resulting from welding and heat-treating.

More >>
Pickling/Chemical Cleaning Services

In our building we have a specially designed containment area to process large components. This enables us to process nearly any part that can be transported to our facility. If this is not feasible we could deploy our On-Site crews to perform this treatment at your facility. For some applications electropolishing may be considered.

Electropolishing is a useful alternative to pickling. Metal removal is achieved by applying electric current to a part submerged in an electrolytic bath. Electropolishing usually creates a bright, smooth and more highly corrosion resistant finish.

Pickling is the chemical cleaning of metallic surfaces in order to remove impurities, stains or scale with an acidic solution. Allegheny Surface Technology uses pickling solutions consisting of nitric (HNO3) and hydrofluoric (HF) acids to remove the scale and underlying chromium depleted layers to restore the corrosion resistance of stainless steel. Mechanical removal of those imperfections may leave abrasive material or other particles embedded in the surface and in some applications mechanical polishing may be impractical.

Pickling is considered the preferred solution for the restoration of the corrosion resistance in stainless steel. Pickling will further create a uniform dull finish on the work piece. Allegheny Surface Technology is also capable of performing localized pickling. For those applications pickling pastes, where the solution is mixed with an inert carrier, are used to treat selected areas such as welds. Examples are parts that just need welds cleaned up or parts which have other than stainless steel components as part of the assembly.

Related Suppliers
Related Product Areas
View More Product Announcements for chromium oxide



Home   |   About GlobalSpec   |   Advertise With Us   |   Site Map   |   Top Categories   |   Terms of Use
Privacy Policy   |   Link To Our Site   |   Submit a Site   |   Recommend This Site
©1999-2008 GlobalSpec.  All rights reserved.  GlobalSpec, the GlobalSpec logo, SpecSearch, The Engineering Search Engine and The Engineering
Web are registered trademarks of GlobalSpec, Inc. The Engineering Toolbar and DesignInfo are service marks of GlobalSpec, Inc.
No portion of this site may be copied, retransmitted, reposted, duplicated or otherwise used
without the express written permission of GlobalSpec Inc.   350 Jordan Rd, Troy, NY, 12180