VCI products prevent corrosion by combining vapor-phase chemistry with physical barrier protection. Together, these mechanisms interrupt the electrochemical reactions that cause rust and oxidation on metal surfaces. ZERUST® VCI products protect metals throughout storage, shipment, and long-term layup without requiring direct contact or surface coatings.
How VCI Products Prevent Corrosion at the Molecular Level
VCI products prevent corrosion by releasing vapor corrosion inhibitor (VCI) molecules into a confined space. These molecules diffuse through the air and actively bond to metal surfaces, forming a protective molecular layer. This layer interferes with electron movement between anodic and cathodic sites on the metal. By doing so, it halts the electrochemical corrosion process before corrosion can begin. Because the inhibitors move in vapor form, they protect visible metal surfaces. They also reach recessed areas, including crevices, cavities, threads, and internal voids. These areas are often difficult or impossible to protect using traditional rust preventatives.
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How VCI Products Prevent Corrosion by Blocking Moisture and Contaminants
In addition to vapor-phase protection, many ZERUST® VCI products provide a physical barrier. This barrier protects metal parts from external corrosive factors. These include moisture, oxygen, dirt, abrasion, and acid gas pollutants commonly found in industrial, marine, and transportation environments.
Depending on the application, ZERUST® VCI materials may incorporate enhanced barrier properties, including reduced moisture vapor transmission, improved tear and UV resistance, static dissipation, and increased mechanical strength. Together, these features help limit the environmental exposure that accelerates corrosion.
Moisture Control and Water Repulsion on Metal Surfaces
VCI products also prevent corrosion by adding water-repellent properties to the metal surface. The protective molecular layer reduces the ability of water to wet the surface, which limits the formation of an electrolyte. Without an electrolyte, corrosion reactions cannot proceed.
VCI products do not absorb standing water, but they significantly reduce corrosion risk from humidity, condensation, and residual surface moisture.
How the Protective VCI Layer Forms and Dissipates
The vapor corrosion inhibitor layer remains effective as long as the metal stays within an enclosure where air exchange is minimal. Ideally, the enclosure allows fewer than one air exchange per day, such as a sealed package or an electrical cabinet opened briefly and infrequently.
Once the metal part is removed from the enclosure, the protective layer gradually dissipates because it is no longer maintained by equilibrium with the VCI source. This typically occurs within about one hour, leaving the metal clean, dry, and corrosion-free, with no residue to remove.
Why VCI Products Outperform Traditional Rust Preventatives
Unlike oils, greases, or wax coatings, VCI products prevent corrosion without direct contact and without altering the metal surface. Parts do not need to be dipped, sprayed, or cleaned before use. This reduces labor, eliminates secondary cleaning steps, and minimizes waste associated with conventional rust prevention methods.
VCI products prevent corrosion even on complex geometries and mixed-metal assemblies, making them well-suited for modern manufacturing, export packaging, and long-term storage applications.
Looking for the Right VCI Products to Prevent Corrosion?
Explore ZERUST® VCI packaging and corrosion prevention solutions designed for storage, shipment, and long-term protection.
Added Protection from Acid Gas Scavenging and Advanced Materials
Some ZERUST® VCI products contain acid-gas-absorbing additives that neutralize corrosive pollutants before they reach the metal surface. These scavenging compounds react with contaminants, such as sulfur dioxide and nitrogen oxides, that may diffuse through packaging materials.
By combining vapor corrosion inhibition, pollutant scavenging, and optimized barrier properties, ZERUST® VCI products provide multi-layered corrosion protection tailored to demanding environments.
When and Where VCI Products Prevent Corrosion Most Effectively
VCI products prevent corrosion whenever metal parts are enclosed with minimized airflow, including during storage, domestic or overseas shipment, and extended equipment layup. Protection begins quickly after enclosure and continues for the designed service life of the product, provided packaging integrity is maintained.
This makes VCI technology especially effective for manufacturers and suppliers seeking reliable corrosion protection without added processing steps or surface contamination.
Apply VCI Technology with Confidence
For help applying VCI technology to your storage, shipment, or layup conditions, contact ZERUST® for expert support.
ICT®510-C Ferrous VCI Film provides cost-effective and targeted protection against rust damage for ferrous metals, such as steel, iron, and cast iron in shipping, storage, and work-in-progress.
ICT®510-C VCI Multimetal Film provides cost-effective and versatile protection against rust and corrosion damage for ferrous and non-ferrous metals in shipping, storage, and work-in-progress.
ICT®510-C Non-ferrous VCI Film provides cost-effective and versatile protection against corrosion damage for non-ferrous metals such as aluminum, copper, brass, and bronze, in shipping, storage, and work-in-progress.
ICT®510-C VCI Film provides cost-effective and versatile protection against rust and corrosion damage for metal assets in shipping and storage. Additionally, it’s available in ferrous, non-ferrous, and multimetal formulations, as well as various-sized rolls, sheets, tubing, and bags.
ICT®510-C VCI Tubing provides versatile protection against corrosion, as the tubing offers a tailored packaging solution for parts of various sizes or long metal assets metals in shipping, storage, and work-in-progress.
Vapor Capsules are portable VCI emitter diffusers containing proven ZERUST® Vapor Corrosion Inhibitors (VCI). They protect metals in hard-to-reach areas of control panels, electrical cabinets, or other enclosed spaces from corrosion, even when they are in operation. Additionally, use these VCI emitter diffusers as a supplement to other ZERUST® VCI packaging products for added protection.
ZAK-M22 Vapor Capsules are portable VCI capsules containing proven ZERUST® VCI technology, used to protect metals in hard-to-reach areas of control panels, electrical cabinets, or any other enclosed spaces from corrosion. Each capsule has a QR code printed on the label to facilitate scheduling its replacement schedule.
Z-PAK® is an economical, effective, and easy-to-use vapor corrosion inhibitor (VCI) diffuser packet that can be used alone or, more typically, with other ZERUST® packaging products to provide robust temporary corrosion protection for ferrous metals during shipment, storage, or work-in-progress.
ICT®432-35P is an acid-free, pH-neutral, and non-abrasive VCI kraft paper coated with a 3/4 mil plain polyethylene layer. As a result, providing the kraft paper with increased tear and moisture resistance, making it an efficient and cost-effective solution for the corrosion protection of multiple metal types during work-in-progress, shipping, and storage.
ICT®430-35SR VCI Scrim Paper is an acid-free, pH-neutral, and non-abrasive VCI kraft paper that’s scrim-reinforced (3/4 mil polyethylene layer and fiberglass scrim). As a result, providing effective corrosion protection with the convenience and affordability of a paper wrapping product with superior strength that avoids ripping and tearing during work-in-progress, shipping, and storage.
ICT®420-35P VCI Poly Kraft Paper is an acid-free, pH-neutral, and non-abrasive kraft paper coated with a one-mil thick ZERUST® ICT® polyethylene layer containing Vapor Corrosion Inhibitors (VCIs). As a result, providing the kraft paper with increased tear and moisture resistance, making it an efficient and cost-effective solution for the corrosion protection of ferrous metals during work-in-progress, shipping, and storage.
ICT®420 is an acid-free, pH-neutral, and non-abrasive VCI kraft paper that merges the practicality and cost-efficiency of paper-based packaging with advanced corrosion protection. Consequently, it streamlines the preservation of metals during work-in-progress, shipping, and storage.
ICT® VCI Poly Bags provide convenient and proven protection against corrosion damage for metals in shipping and storage. In addition, they are available in ferrous, non-ferrous, anti-tarnish, and multimetal protection types and various zipper, flat, and gusseted sizes.
ICT® VCI Tote Covers are a convenient packaging product made of ZERUST® VCI film with an elastic band designed to provide a secure fit over totes and odd-shaped or protruding parts such as hub assemblies, protecting against corrosion, dirt, dust, smoke, and other contaminants while keeping them visible and easy to access.
ICT® Tube Strip is a flexible hollow plastic VCI emitter tubing product containing ZERUST® Vapor Corrosion Inhibitor technology. They are used to protect narrow tubes, pipes, and other enclosed spaces from corrosion or as a supplement to other ZERUST® VCI packaging products for added protection.
ICT®510-C VCI Weapon Bags are specifically designed to protect weapons, including handguns, rifles, as well as accessories, against corrosion, dust, sand, and humidity damage in shipping, storage, and between operations.
ICT® Plastabs® are thin, light, rigid polyethylene VCI emitter plastic tabs that are made with ZERUST® Vapor Corrosion Inhibiting (VCI) technology. Their small, thin shape makes Plastabs® perfect for protecting critical surfaces within narrow or hard-to-reach areas of electronics or parts of equipment or as a supplement to other ZERUST® VCI packaging products for added protection.
ICT® Open Cell VCI Foam Emitter Pads are a convenient way to provide added corrosion protection in packaging or an effective way to improve protection in demanding environments and on lightly contaminated parts.
