Carbon Steel vs. Galvanized Steel

Carbon steel is a strong, durable material widely used for its toughness and versatility. Galvanized steel is suitable for outdoor and corrosive environments as the zinc coating prevents rust. They are different materials for multiple uses.

This article will help you understand the differences between them.

Composition of Carbon Steel vs Galvanized Steel

The difference in chemical composition between carbon steel and galvanized steel is primarily due to the zinc coating on galvanized steel and the varying carbon content in carbon steel.

Galvanized steel uses a mild steel base, usually with less than 0.3% carbon, making it relatively soft and easy to work with. This base is then coated with a thin layer of zinc, which serves as a protective barrier against corrosion.

Carbon steel, in contrast, is classified based on its carbon content, which influences its hardness and strength. It includes three main categories: low-carbon steel (less than 0.3% carbon), medium-carbon steel (about 0.3% to 0.6% carbon), and high-carbon steel (over 0.6% carbon). 

Key Differences Between Carbon Steel And Galvanized Steel

When choosing between galvanized steel and carbon steel for your project, it’s important to consider factors like corrosion resistance, durability, and cost. 

To help you make an informed decision quickly, we’ve provided a concise comparison table below, highlighting the key differences between the two materials. 

Properties of Carbon Steel vs Galvanized Steel

Corrosion Resistance—Galvanized Steel Is Better

Galvanized steel is much more corrosion-resistant than carbon steel. The zinc layer on galvanized steel serves as a shield, protecting it from rust and corrosion. In contrast, carbon steel, without any coating, rusts quickly when exposed to moisture or air. 

The zinc in galvanized steel also sacrifices itself first to corrosion, further protecting the underlying steel. 

Strength—Carbon Steel Is Stronger

Carbon steel is typically stronger than galvanized steel. The zinc coating on galvanized steel is softer, making it more prone to scratches or dents compared to the harder surface of carbon steel. Therefore, carbon steel is preferred when maximum strength is needed.

Weldability—Low-carbon Is Best

Low-carbon steel is the most weldable in both galvanized and non-galvanized forms.

Galvanized steel can be more difficult to weld. Because it has a zinc coating, which can produce toxic fumes when welded. The zinc coating on galvanized steel can also interfere with the weld quality, causing issues like weak joints or excessive spatter. 

High-carbon steel is more difficult to weld than galvanized Steel. Higher carbon content increases hardness but decreases weldability, requiring special techniques like preheating and post-weld heat treatments to reduce cracking risks.

Surface Appearance

The zinc coating on galvanized steel creates a textured pattern that is often shiny and irregular.  The spangled finish on galvanized steel is a result of the zinc crystallization process during coating, making it easy to identify.

In contrast, carbon steel has a uniform, polished look but can develop a dull appearance over time due to rusting.

For galvanized products like steel pipes, and sheets, it’s essential to inspect the coating thoroughly to ensure uniform coverage and proper adhesion, as any flaws or inconsistencies in the zinc layer can affect corrosion resistance.

Cost—Carbon Steel Is Cheaper

Galvanized steel is more expensive than carbon steel because of the added cost of the zinc coating process. While carbon steel is cheaper upfront, it might lead to higher maintenance expenses over time because it tends to rust and corrode. Galvanized steel, though pricier initially, can save on long-term costs by reducing the need for repairs or replacements in harsh environments.

Manufacturing Process of Carbon Steel vs Galvanized Steel

The main difference in Manufacturing is the zinc coating process. Carbon steel is produced by combining iron and carbon, then shaped into desired forms through rolling or forging. 

Galvanized steel can be produced using different types of galvanizing processes, each adding a zinc coating to the steel in a specific way. The main methods include:

• Hot-dip galvanizing

Carbon steel will be dipped into a bath of molten zinc. The steel is coated with a thick, durable zinc layer that offers excellent corrosion protection. 

• Electro-galvanizing

It involves applying a thin layer of zinc to the steel surface using an electric current. The coating is more uniform and smooth but thinner compared to hot-dip galvanizing. 

Application of Carbon Steel vs Galvanized Steel

Galvanized Steel Applications:

• Outdoor structures like fences, gates, and poles
• Roofing and wall panels in construction
• Automotive body parts, especially in areas prone to rust
• HVAC ductwork and piping
• Electrical equipment housings
• Guardrails and highway barriers
• Agricultural equipment exposed to moisture

Carbon Steel Applications:

• Structural beams and frames in construction
• Machinery and heavy equipment parts
• Automotive components such as engine parts and axles
• Industrial tools and cutting equipment
• Pressure vessels and tanks
• Pipes for gas and oil industries

Suppliers for Galvanized Steel and Carbon Steel

Steel Pro Group is your reliable partner for high-quality galvanized and carbon steel products. We offer a wide range of steel products like G60, G90 galvanized steel, and S235 carbon steel.

Our products are crafted to the highest standards for durability and performance. With our careful attention to packaging, we ensure every item arrives intact and ready for use.