ThePipingMart Blog Grades CR45 Steel – Composition, Properties, and Uses

CR45 Steel – Composition, Properties, and Uses

Cr45 Steel

Steel is critical in almost every field, from construction to manufacturing, automotive to aerospace industries. Among various types of steel, Cr45 steel is popular for its excellent mechanical and physical properties. But what is Cr45 steel, and what makes it stand out compared to other steels? This article will explore the composition, physical and mechanical properties, uses, and Heat Treatment of Cr45 steel.

What is CR45 Steel?

Cr45 steel is a high-carbon steel alloy with a chromium content of approximately 0.45 %. The high carbon content imparts significant strength and hardness to the material while adding chromium enhances its corrosion resistance and overall durability. Cr45 steel is commonly used in applications requiring high strength, toughness, and resistance to wear and tear.

CR45 Steel Composition

Cr45 steel is an iron, carbon, and chromium alloy with phosphorus, sulfur, and manganese as the other essential elements. The carbon content of Cr45 steel ranges from 0.44% to 0.48%, while the maximum allowable amount of phosphorus and sulfur is 0.035%.


Si  Mn P Ni Cr S Cu As Fe


<0.25 <0.25
<0.25 <0.08

CR45 Steel Physical Properties

The physical properties of Cr45 steel are notable, including its excellent heat resistance, corrosion resistance, and high tensile strength. The density of Cr45 steel is 7.85 g/cm³, with a melting point of 1425 °C.

CR45 Steel Mechanical Properties

The mechanical properties of Cr45 steel make it favourable for many applications. The specific tensile strength of Cr45 steel ranges from 400 to 800 Newtons per square millimetre (N/mm²), depending on the manufacturing process. The yield strength is between 220 to 665 N/mm², and the elongation is around 15 per cent.

Standard Delivery condition Creep limit, Rm (MPa) Short-term tensile strength ReH (MPa) Minimum elongation ratio σ, % Contraction ratio, %
GOST 1050 Post-normalisation 355 600 16 40
DSTU 7809 Post-normalisation 355 600 16 40

CR45 Steel Uses

Cr45 steel is used in various industrial applications due to its strength and other properties. High-stress applications like ball bearings, die-casting components, gearwheels, cutting tools, drills, and concrete reinforcing bars often use Cr45 steel. It is also used to construct buildings, bridges, and other civil engineering structures.

CR45 Steel Hardness

The hardness of Cr45 steel is an important factor in its selection for different applications. In the annealed condition, Cr45 steel has a hardness of 187 Brinell. After quenching and tempering, the hardness of this steel can reach 600 Brinell or higher, making it suitable for high-wear applications.

CR45 Steel Heat Treatment

Heat treatment is critical in making Cr45 steel suitable for various applications. The heat treatment involves heating the steel to its critical temperature, followed by quenching and tempering to achieve the desired hardness and strength properties. Depending on the application, different heat treatment processes are used, such as annealing, normalizing, and hardening.


Cr45 steel is a high-strength, high-carbon steel alloy with chromium that offers excellent mechanical and physical properties. The correct selection of this steel can provide outstanding results in various applications. Understanding its composition, physical and mechanical properties and heat treatment process can help engineers and manufacturers select and apply this steel properly.

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