Since the dawn of time, mankind has battled a seemingly unstoppable enemy: corrosion. (Granted, there are actually a number of seemingly unstoppable enemies that mankind has and continues to face—the passage of time, the ravages of old age, the Morlocks, etc.—but we’ve got to tighten up the focus or this piece would be about 900,007 words long.)
Corrosion for One & All
Wood from the tallest, strongest trees will rot. The mightiest, most powerful iron locomotives will rust. Even stone, proverbially the sturdiest of them all, will deteriorate over time. What, then, can man do? How, then, can man prevent corrosion from, um, corroding everything with which he comes into contact?
One of the earliest forms of corrosion protection was tar. Slathered onto the undersides of sailing ships, it protected the wooden hulls against salt water’s harmful effects. After mankind got all Industrially Revolutionized, and metal became a more common material of construction, paint was used not just to make stuff look pretty, but to combat the air and water exposure that would oxidize the metal and rust it away.
Science to The Rescue (As Usual)
While the march of scientific advancement has actually created more corrosion problems—harsh chemicals, high-friction factory processes, etc.—it has also led to countless advances in corrosion protection.
Materials scientists have created a number of engineered coatings which can be added to nearly any substrate material to guard against corrosion. Corrosion resistant coatings can be engineered to provide more effective protection against a certain type of corrosion or for a specific type of material.
For example, a coating designed to protect steel against salt water exposure would consist of wildly different chemicals and components than would one designed to protect aluminum from corrosion caused by part-on-part friction in a piece of manufacturing equipment.
Interestingly, though the composition of these coatings can vary wildly, as can the materials to which the coatings are applied, the method of application is almost always the same: spray coating. In practice, these spray coatings are roughly analogous to spray painting—point the nozzle at whatever you want to coat and spray away. However, the science behind these applications is far more sophisticated, often involving coating particles that move at hundreds of feet per second, electrical plasma streams, or other technologically advanced techniques.