Corrosion Prevention Information
     Corrosion is a term that refers to the gradual wearing away of metal through the electrochemical process of oxidation (or rusting). This condition readily occurs while products made from metals and alloys are in transit or storage if not properly protected.
     Iron and other steels are made from natural occurring Iron Oxide. Steel is an alloy of iron made by combining iron, carbon and other trace elements. Rust is actually Iron Oxide that is created on the surface of iron or steel by an electrochemical process that occurs when the metal is in the presence of water and oxygen. The water-oxygen combination forms a thin film of electrolytes on the surface of the metal. The electrolyte film causes an electrical circuit to be completed that allows the metal to exchange electrons and revert back to its natural state or Iron Oxide. This electrolyte film is formed when a critical humidity level is reached. For iron the critical level is 60% relative humidity, (in unpolluted atmospheres). Temperature, pollutants and deposits on the surface all play in the process. The resulting corrosion that occurs causes wide spread damage to products ranging from cosmetic blemishes to severe surface degradation. The effects can also cause non-performing contact points on electrical components. $300 billion dollars is spent by US industries every year combating the formation of or cleaning oxidation from products made from iron and its alloys. Prevention is the least expensive method of combating corrosion damage. The cost of protective packaging is many times less than the cost to clean and remove rust once a product is at the customers site. The general rule is to maintain less than 40% relative humidity to keep oxidation to a minimum.
What Are VCI's?
     VCI stands for volatile corrosion inhibitor which is actually a formulation of elements that act to prevent volatile corrosive gasses from reaching a metal surface. Examples of those gasses are oxygen, moisture vapor, and hydrogen sulfide which are abundant in the atmosphere. VCI chemistry works at the molecular level. VCI molecules will condense onto a metal surface and form a protective layer that insulates the metal from corrosion-causing contaminants.

How VpCI's Work
     VpCI stands for Vapor Phase Corrosion Inhibitor. This is a type of volatile corrosion inhibitor whose molecules migrate out of a source material and vaporize into the surrounding atmosphere. When the vaporization occurs inside of a sealed package a high concentration of VpCI molecules conditions the interior atmosphere of that package for metal preservation. Metals attract VpCI molecules to their surfaces where a reaction takes place that coats the metal surfaces with a one molecule thick layer of VpCI molecules. This coating of molecules prevents corrosion causing elements, such as moisture or salts, from contacting the metal surfaces and thus prevents corrosion. The VpCI molecules are small and highly attracted to metals. They will maneuver around other substances such as salts, oxygen, and water to reach the metal’s surface. Thus, pinholes and small rips in a cover will not greatly diminish the effectiveness of the VpCI chemistry if the air exchange between the interior of the cover and the exterior environment is limited. The diagram below illustrates how VpCI's work inside of a barrier package.