Product details table:

Physical and Chemical Properties

Physical properties

Appearance:

It usually presents a metallic gray color, with a smooth surface after processing. Different surface treatments, such as painting, galvanizing, or polishing, can be applied to achieve specific aesthetic or functional effects.

Density:

The density of Q235 carbon steel is approximately 7.85 g/cm³, which is slightly lower than stainless steel but still ensures good strength and structural stability.

Melting point:

The melting point of Q235 carbon steel is around 1495-1520℃, making it suitable for high-temperature applications but requiring protection in extreme environments to prevent oxidation.

Coefficient of thermal expansion:

The coefficient of thermal expansion is moderate, typically around 11.7×10⁻⁶/℃ at room temperature. This characteristic allows Q235 steel plates to maintain dimensional stability under normal temperature fluctuations.

Thermal conductivity:

Q235 carbon steel has relatively good thermal conductivity, with a coefficient of about 50-60 W/(m·K). This makes it suitable for applications involving heat transfer, such as boilers or heat exchangers.

Electrical conductivity:

It has moderate electrical conductivity, which is typical for carbon steel. The conductivity is significantly lower than copper or aluminum, making it unsuitable for electrical applications but acceptable for general structural use.

Chemical properties

Corrosion resistance:

Q235 carbon steel has limited corrosion resistance compared to stainless steel. It is prone to rusting when exposed to moisture or corrosive environments. Surface treatments like painting, galvanizing, or coating are often applied to enhance its corrosion resistance. For example, galvanized Q235 steel plates are widely used in outdoor structures to resist atmospheric corrosion.

Antioxidation:

At room temperature, Q235 steel exhibits moderate oxidation resistance. However, at higher temperatures, it is susceptible to oxidation, requiring protective coatings or alloying elements to improve performance in high-temperature environments.

Chemical stability:

In general chemical environments, Q235 carbon steel has moderate chemical stability. It reacts easily with strong acids, such as hydrochloric acid or sulfuric acid, leading to corrosion. In alkaline or neutral environments, it shows better stability, but additional protection is needed for harsh chemical conditions.

Passivation:

Unlike stainless steel, Q235 carbon steel does not naturally form a passivation film. To improve its corrosion and oxidation resistance, surface treatments such as galvanizing, painting, or applying anti-corrosion coatings are essential. These treatments act as a barrier to prevent direct contact between the steel and corrosive agents.

Application:

Q235 carbon steel plates are widely used due to their excellent mechanical properties, affordability, and ease of processing. In the construction industry, they are commonly used for structural components, such as beams, columns, and reinforcement bars, ensuring the stability and durability of buildings. In machinery manufacturing, Q235 steel plates are processed into parts like frames, bases, and supports, providing reliable performance. In the automotive industry, they are used to manufacture vehicle frames and chassis due to their high strength-to-weight ratio. Additionally, in the fields of shipbuilding, bridges, and pressure vessels, Q235 steel plates are indispensable. They are also used in storage tanks, pipelines, and other industrial equipment, where cost-effectiveness and versatility are critical. Surface-treated Q235 steel plates are ideal for outdoor structures, such as fences, gates, and utility poles, offering long service life with proper maintenance.