Understanding the Causes of Rust in Metals

Rust is an all-too-common issue, visible on everything from old gates to vehicles in the junkyard. This familiar sight is usually a sign of metal items that have not been adequately maintained. Rust can affect a variety of metal surfaces, including car bodies and tools, leading to structural damage and visual degradation. The process of rusting occurs at the chemical level when metal is exposed to moisture and oxygen, a reaction that causes the metal to weaken, discolor, and deteriorate over time. This article will further explain the causes and effects of rust, and discuss effective measures for preventing it, ensuring the longevity and value of metal structures such as bridges and boats.

Inspiration taken from D&D Coating

Why Does Metal Rust?

Metal rusts primarily due to a chemical reaction called oxidation. This occurs when iron, present in metal surfaces, reacts with oxygen and water to form iron oxide, commonly known as rust. The equation representing this reaction is: iron + oxygen + water = iron oxide (rust).

Rust is a type of corrosion that affects iron-containing metals like steel, iron, and cast iron. It can develop on any exposed metal surface and is accelerated by moisture, including humidity in the air. The rate at which rust forms depends on several factors, including the level of humidity, the amount of oxygen present, and the type of metal.

Without intervention, rust can progress, eventually corroding metal into a brittle oxide powder. This deterioration significantly shortens the lifespan of the metal and compromises its structural integrity. Protective measures such as coatings, including zinc-rich cold galvanizing compounds, can help mitigate rust formation and prolong the life of metal structures.

Preventing Rust With Cold Galvanizing Compound

Cold galvanizing compound offers robust rust prevention by leveraging its high zinc content. Unlike conventional paint, which lacks sufficient zinc for effective corrosion prevention, cold galvanizing compound contains a high percentage of zinc, a less noble metal compared to steel. When applied via spray or brush, this compound forms a protective barrier on steel surfaces, effectively shielding them from the elements and preventing corrosion.

As zinc corrodes, it creates a hydroxycarbonate salt that bonds with existing zinc in the coating, ensuring ongoing galvanic protection. This advanced, self-healing film not only provides immediate protection but also continues to guard against rust and corrosion over time. Additionally, the high zinc content and non-encapsulated particles enable galvanic corrosion protection similar to hot-dip galvanizing, ensuring thorough and long-lasting rust prevention. Unlike hot-dip galvanizing, which requires controlled settings, cold galvanizing compound can be conveniently applied on-site straight from the can, resembling the application process of paint.

Different Methods For Applying Rust Prevention

After application and drying, Cold Galvanizing Compounds maintain the same high standard of corrosion prevention, whether they are sprayed on or applied by brush. Different formulations are available for specific use cases. Once the ideal product for your needs is determined, two application options are available:

Brush Application for Rust Prevention

Brush application for rust prevention offers a hands-on approach to safeguarding metal surfaces from corrosion. This method involves directly applying a protective coating, such as cold galvanizing paint, onto the metal using a brush. It allows for meticulous coverage, ensuring that every nook and cranny is properly sealed against rust formation. Brush application is particularly advantageous for intricate or irregularly shaped surfaces where spray application may be less effective. Additionally, it provides greater control over the thickness of the coating, allowing for tailored levels of protection based on the specific needs of the metal structure. This hands-on technique not only ensures thorough protection but also allows for a more tactile and personalized application process, making it a preferred choice for many rust prevention projects.

Spray Application for Rust Prevention

Spray application for rust prevention offers a convenient and efficient method to protect metal surfaces from corrosion. Cold galvanizing spray can be administered in aerosol form or using a compressor or airless spray techniques. This application option is sought after for various reasons, including ease of use and portability.

Unlike traditional brush application methods, spray cans are lightweight and easy to transport, making them ideal for applications where mobility is a concern, such as climbing ladders or working in tight spaces. Additionally, aerosol application ensures consistent coverage and dry film thickness, yielding superior performance comparable to brush-on application. Overall, spray application is a versatile and effective technique for rust prevention, offering convenience and reliability in various scenarios.

Unleashing Zinc's Power

Zinc, often underestimated, stands as a stalwart guardian against corrosion, ready to defend metal surfaces with unwavering resilience. Its remarkable properties make it a cornerstone in rust prevention strategies, forming protective barriers that shield against the relentless assault of moisture and oxygen.

Rust prevention is crucial for any type of commercial metal, as unchecked corrosion will eventually cause significant damage to the structural integrity of the metal and compromise its integrity over time. Cold galvanizing compounds are coatings utilized to create a protective barrier against rust and corrosion on metal surfaces like bridges, cell towers, boats, and other marine structures. These compounds contain zinc particles that are suspended in a liquid carrier, in this case paint. When applied to a metal surface, the zinc particles adhere to the surface and form a protective layer that acts as a “sacrificial anode.”

A sacrificial anode is a metal that is more reactive than the metal it is protecting. In the case of cold galvanizing compounds, the zinc takes on this role and corrodes instead of the metal surface of your gate, bridge, or other metal structure. When these zinc particles corrode, they create a passive layer on the surface of the metal which prevents further corrosion and protects your steel from corrosion. The result? A reliable solution to safeguarding metal surfaces from rust and corrosion.


Curious about rust prevention? Dive into our blogs for insightful tips on keeping metal structures pristine. And while you're at it, explore our diverse range of topics covering everything from metal signage to fabrication. There's plenty to discover!