What is the Difference Between Black Steel and Mild Steel

The key difference between black steel and mild steel is that black steel has a dark blue and oily surface, whereas mild steel has a silvery gray and non-oily surface.

Steel is an alloy of iron, carbon, and some other chemical elements. The carbon content in this alloy ranges up to 2% by weight. The most important properties of this alloy are high tensile strength and low cost. This is the most common material for building infrastructure. In addition, it is useful for the production of tools for construction as well.

1. Overview and Key Difference
2. What is Black Steel
3. What is Mild Steel
4. Black Steel vs Mild Steel in Tabular Form
5. Summary – Black Steel vs Mild Steel

What is Black Steel?

Black steel or black carbon steel is a metal alloy or a mixture of iron and carbon along with some other metals in small quantities. Generally, pure iron is soft even though we can melt it and shape it into desired shapes. The addition of carbon to pure iron can increase the strength of the metal, and most carbon steel types contain 1-2% of carbon. Typically, black steel is made during the production process of steel, where a high temperature can create a thin layer of iron that is oxidized. This oxidized iron layer is created on the outer surface of the steel.

Typically, iron tends to react easily with oxygen in the air. This reaction creates iron oxide, commonly called rust. This rust formation can cause the failure of some parts of iron. Therefore, the surface of iron is often coated to prevent surface rust formation. An important advantage of black steel is its natural anti-corrosion property, which comes from black iron oxide coating. The oxide layer can act as a barrier to keep oxygen from the iron layer that lies below. This thin oxide layer forms at a high temperature, so the iron does not require any coating.

Black steel is commonly used for gas or water utility piping. This is because black steel has a low cost of production, and it can also easily be welded using simple, common methods. Typically, some long-distance piping systems use this steel which can prevent rusting quickly. Moreover, we can use black steel in climates or ground conditions that are available in changing or accelerating corrosion. However, we may sometimes need additional coatings or prevention methods.

What is Mild Steel?

Mild steel is a very common type of carbon steel that has a low amount of carbon by weight. The amount of carbon in this steel is around 0.2%. The other major elements present in it are manganese, silicon, sulfur, and phosphorus. Mild steel is mainly useful in the industry. However, we also use this material in the equipment we use in our day-to-day life.

An important property of mild steel is that it is not brittle. Moreover, it does not readily undergo a tempering process and has considerable strength. In addition, it is a good electrical conductor. Therefore, we can use it in welding. Moreover, it has high malleability because of the low carbon content. Due to its ferromagnetic properties, we can easily magnetize mild steel. Furthermore, this material is suitable for structural purposes. However, compared to low-carbon steel, this material has more carbon and is prone to corrosion.

What is the Difference Between Black Steel and Mild Steel?

Black steel or black carbon steel is a metal alloy or a mixture of iron and carbon along with small quantities of some other metals. Mild steel is a very common type of carbon steel that has a low amount of carbon by weight. The key difference between black steel and mild steel is that black steel has a dark blue and oily surface, whereas mild steel has a silvery grey and non-oily surface.

The below infographic presents the differences between black steel and mild steel in tabular form for side by side comparison.

Summary – Black Steel vs Mild Steel

Steel is an alloy of iron and carbon along with some other chemical elements. The carbon content in this alloy ranges up to 2% by weight. The key difference between black steel and mild steel is that black steel has a dark blue and oily surface, whereas mild steel has a silvery gray and non-oily surface.