All the latest news from the industry weekly compiled by the editorial team for you free of charge.
This eMail is already registered.
An unexpected error occured.
Please accept our Terms of Use.
Registration successful.
1 Rating

CORROSION PROTECTION IN METAL FABRICATION INDUSTRY Controlling corrosion in a high humid & moist atmosphere

Jul 28, 2022

High moisture content is one of the major contributing factors that lead up to corrosion. Thus, it becomes extremely challenging to control corrosion in a moist atmosphere. Areas that receive high rainfall or are in proximity to a sea usually have fluctuating temperatures and very high moisture content. Thus, corrosion protection is an important issue in the metal fabrication industry serving automotive & OEMs, where parts are dispatched for machining, assembly, or storage.

Corrosion is a process that converts a manufactured metal into its naturally occurring oxidation state. Corrosion leads to gradual destruction by catalysing chemical and/or electrochemical reactions. Atmospheric corrosion is defined as an electrochemical process that depends on the presence of electrolytes when dissolved in a polar solvent, such as water, which may be in the form of rain, dew, humidity, or melting snow. The dissolved electrolyte separates into cations and anions, which disperse uniformly throughout the solvent, making corrosion prevention further complicated.

The moisture acts as a carrier that facilitates the flow of electrons. Corrosion does not occur in dry air because of the presence of air alone. However, a problem arises when the metal reacts with a certain amount of water vapour present in the air. This water vapour or moisture in the air is measured in terms of relative humidity (RH). Metal tends to corrode when water molecules present in the air condense and settle on the surface of that metal due to a relatively lower surrounding temperature. Higher humidity leads to higher condensation on the metal surfaces.

Corrosion prevention methods

Corrosion can occur at any stage, during the input, or the manufacturing process, storage, shipment, or usage. Below mentioned are some of the most popular corrosion prevention methods:

  • Barrier coatings: Paint, plastic, or powder

  • Surface coatings: Tin plating, galvanisation, copper plating, etc

  • Metallurgy: Alloyed steel, stainless steel

  • Temporary barrier protection: Rust preventive oil, VCI or Volatile Corrosion Inhibitor, etc

Temporary barrier protections are conventional rust prevention methods that offer effective corrosion control over a short time in the automotive and auto component industry. This is because it allows for flexibility in application, excellent confluence with upstream and downstream requirements, and is very economical.

NOX-RUST® rust preventive oils, wax, coatings, etc are based on the CCI or Contact Corrosion Inhibition technology and have proven to be instrumental in temporary corrosion prevention and control for automotive and engineering parts. Based on the concept of polarity and thin-film technology, the Daubert proprietary polar molecules do not allow any oxidising elements to permeate even under condensing climates and can survive thermal stresses beyond most other rust preventive oils.

Eliminating corrosive effects

The exceptional ability of NOX-RUST® to remove preexisting moisture and light alkaline coatings from the metal surface further augments its performance. NOX-RUST® offers a broad range of rust preventives which, besides corrosion prevention, can also be selected based on needs such as water displacement properties, film thickness, upstream and downstream compatibility requirements, and many more.

Similarly, Daubert’s VCI® technology is based on the concept of volatility and polarity and performs favourably even in the presence of moisture. This unique technology enables Daubert to form a complex with moisture and negate its corrosive effects. Products based on this technology are available in various forms such as VCI oils, packaging papers and films, emitters, and powders, which allow their use in multifarious applications across a broad spectrum of industries and at different stages in the life cycle of a product.

An optimised and effective corrosion protection method can be developed by the Daubert Solution Engineering team which can further get validated by various accelerated corrosion tests and field trials.

Courtesy: Zavenir Daubert

Image Gallery

Companies related to this article
Related articles