Product Details Table:

Physical and Chemical Properties

Physical properties

Appearance:

It usually presents a metallic gray color, with a smooth or slightly textured surface depending on the finishing process. Different surface treatments, such as shot blasting or painting, can be applied to enhance its appearance and corrosion resistance.

Density:

The density of Q345 carbon steel is approximately 7.85 g/cm³, which is typical for most carbon steels. This value is slightly lower than stainless steel but still provides excellent strength-to-weight performance.

Melting point:

The melting point of Q345 carbon steel is relatively high, generally around 1450-1520℃. This high melting point ensures its stability in high-temperature environments, making it suitable for structural applications.

Coefficient of thermal expansion:

The coefficient of thermal expansion is moderate. In the range of room temperature to 100℃, the coefficient of thermal expansion of Q345 carbon steel is approximately 11.7×10⁻⁶/℃. This feature allows it to maintain good dimensional stability under varying temperatures.

Thermal conductivity:

The thermal conductivity of Q345 carbon steel is relatively good compared to stainless steel, with a thermal conductivity coefficient of approximately 50-60 W/(m·K). This makes it suitable for applications where heat dissipation is required.

Electrical conductivity:

Q345 carbon steel has moderate electrical conductivity, but it is not typically used for electrical applications due to its higher resistivity compared to copper or aluminum.

Chemical properties

Corrosion resistance:

Q345 carbon steel has limited corrosion resistance compared to stainless steel. Without additional protective coatings or treatments, it is susceptible to rusting in humid or corrosive environments. However, surface treatments such as galvanizing or painting can significantly improve its corrosion resistance.

Antioxidation:

At room temperature, Q345 carbon steel exhibits moderate oxidation resistance. However, at higher temperatures, it may form oxide layers that reduce its mechanical properties. Protective coatings or alloying elements can enhance its oxidation resistance.

Chemical stability:

In general chemical environments, Q345 carbon steel shows moderate chemical stability. It is not resistant to strong acids or alkalis, such as hydrochloric acid or sulfuric acid, and may corrode rapidly in such media. Proper protective measures are necessary for use in aggressive chemical environments.

Passivation:

Unlike stainless steel, Q345 carbon steel does not naturally form a passive oxide layer. However, surface treatments such as phosphating or coating can provide a protective layer to improve its resistance to environmental factors.

Application:

Q345 carbon steel plates are widely used in various fields due to their excellent mechanical properties, weldability, and cost-effectiveness. In the construction industry, they are used for structural beams, bridges, and building frameworks, ensuring high strength and durability. In machinery manufacturing, they are processed into components such as gears, shafts, and pressure vessels, ensuring reliable equipment performance. In the automotive industry, Q345 steel is used to manufacture vehicle frames and chassis due to its toughness and impact resistance. Additionally, in the fields of shipbuilding, oil and gas pipelines, and heavy machinery, Q345 carbon steel plates are indispensable. They are used to fabricate tanks, pipelines, and structural supports, adapting well to demanding working conditions.