How Car Rust Inhibitors Work

January 27, 2012

Any car that’s been owned for any significant period of time is bound to develop car rust at some point. This is especially true for older models that came out before the development of today’s more sophisticated forms of rust inhibitor. However, even later car models can develop car rust. Any significant period of time that a car is left neglected can be enough for rust to take a foothold on one of the weak spots in your car rust protection. That’s why it’s important for all serious car owners to have at least a general idea of how rust inhibitors work. This information can be invaluable to the protective care you give to your car. 

What Is a Car Rust Inhibitor? 

While there are a number of different kinds of rust inhibitor, they are all chemical compounds that are added to a gas or fluid and act to decrease the rate at which a metal or an alloy corrodes. An inhibitor’s effectiveness is determined by the fluid’s composition, the amount of water in the system, the inhibitor’s flow regime and a number of other factors. Up to 99% efficiency can be reached if the correct type and amount of inhibitor are applied. The correct type of rust inhibitor to apply in a given situation depends on a number of aspects, such as the material it is to be applied to and the nature and temperature of the substances that are to be added to it. 

How Car Rust Inhibitors Work 

Different car rust inhibitors work differently. However, three of the most common ways that inhibitors work are as follows:

  1. Some rust inhibitors work by forming a thin, protective film on the metal’s surface. This film keeps corrosive substances from coming in direct contact with your car’s metal.
  2. Other inhibitors inhibit either the reduction or the oxidation of the corrosion system.
  3. Still other inhibitors slow rust formation by absorbing the oxygen dissolved in the system.

Methods of Car Rust Inhibitor Application 

Car rust inhibitors are applied with three different methods. The correct application method depends on the size and shape of the part to be coated, as well as the nature of the inhibitor that is being applied. The three inhibitor application methods are spray coating, dip application and flow coating. 

  1. The first, and most common, application method involves the familiar spray coating. The given rust inhibitor is placed in a solvent or water-based solution, which is then sprayed onto the car metal surface. The spraying equipment disperses the solution into a cloud of atomized particles, which is then spread evenly on the metal surface.
  2. Dip application is used to apply single coats and primers. The process involves, as the name implies, dipping the piece to be coated in a bath. The piece is then drained and force-dried or baked to solidify the coat.
  3. Flow coating is used on pieces that are too large to be dipped and of a shape that would make spray coating difficult or impossible. The process involves conveying the piece through a chamber, where it is flooded with the rust inhibitor with low-pressure nozzles. Unlike spray coating, this process doesn’t involve atomization of the coating substance.

While the application of a rust inhibitor on your car is definitely imperative to keeping it rust-free, it cannot act alone. Keeping your car as clean as possible with regular washing is still the best and cheapest form of car rust protection.