Mechanical properties of steels

Las pMechanical properties are fundamental to the wide use of steel, as they determine its behavior under various loads and forces. These properties include tensile strength, which measures the steel’s ability to withstand forces without breaking; hardness, which indicates its resistance to surface deformation; ductility, which reflects its ability to deform before fracturing; and toughness, which measures its ability to absorb energy before failing. These characteristics are essential for the selection and use of steel in industrial and structural applications and in the manufacture of special steels.

Main mechanical properties of steels

1. Hardness

Hardness, which measures a material’s ability to resist friction and abrasion, is key to wear resistance. Although often confused with strength and toughness, hardness has a different meaning in the context of abrasion-resistant steel.

2. Tenacity

Toughness is the ability of a material to absorb energy without fracturing, resisting breaking under stress. Measured in pounds per foot per square inch or joules per square centimeter, it is critical to distinguish it from hardness, as a material can be very strong without necessarily being hard.

3. Creep resistance

Yield strength is the measure of the force required to initiate permanent deformation of a material, marking the point where it changes from elastic to plastic deformation.

4. Tensile strength

Tensile strength measures the force required to break a material, providing key information about the steel’s durability and ability to withstand stress.

5. Elongation (or ductility)

Elongation, or ductility, measures how much a material can be stretched or compressed before breaking. Expressed as a percentage, it falls between tensile strength and yield strength, reflecting the flexibility of the material before breaking

Factors influencing mechanical properties

The mechanical properties of materials are influenced by various factors.

Understanding these factors helps to select the right material for specific applications and to predict how materials will behave under various conditions.

The following are the key factors that influence the mechanical properties of steels:

• Chemical composition
• Heat treatments
• Manufacturing processes
• Microstructure
• Tempering and annealing
• Presence of impurities
• Grain size
• Cooling rate
• Residual stresses
• Deformation processes (rolling, forging, etc.)