Steel structure properties

Steel is an alloy composed of iron and carbon, and its specific properties can be adjusted by adding various elements such as manganese, sulfur, copper, phosphorus, chromium, and nickel. Therefore, steel structure properties depend on its chemical components.

The influence of different chemical components on steel is as follows:

Increasing the carbon and manganese content will enhance tensile strength and yield strength but reduce ductility and make it less weldable.

If the sulfur and phosphorus content exceeds a certain percentage, it will create brittleness, affecting weldability and fatigue strength.

Chromium and nickel content contribute to the corrosion resistance of steel and can also improve its high-temperature resistance.

Corrosion resistance can be further enhanced by adding copper.

Minor changes in chemical composition can result in various types of steel. These types of steel are used to construct structural components such as pipes, plates, conduits, bolts, rivets, reinforcing bars, and more.

Heat treatment and alloying processes are employed in steel production to achieve different properties and strengths:

· Tensile strength: The stress-strain curve of steel is typically obtained by conducting tensile tests on any standard steel sample. The tensile strength can be determined based on yield strength and ultimate strength.

· Hardness: Hardness is considered the resistance to indentation and scratching of any material. Different methods to measure the hardness of metals include Brinell hardness testing, Vickers hardness testing, and Rockwell hardness testing.

· Toughness of notches: It is the ability to develop very small cracks in the material or materials that can develop such cracks due to several load cycles. These cracks can lead to sudden structure collapse and are very dangerous. Therefore, to ensure this does not happen, preference should be given to materials with slow crack propagation. These types of steel are called high-strength steel, and the amount of energy it absorbs is measured by impacting a notched sample.

· Fatigue strength: A part of the structural building designed to withstand a single static load may fail if that load acts in cycles with a large number.

· Corrosion resistance: Metal corrosion is a natural phenomenon that occurs rapidly in places with high humidity and near salt water. Therefore, efforts have been made to control corrosion using galvanized steel bars and epoxy coatings. Still, they have failed in practical use due to the risk of dispersion and rapid corrosion. Anti-corrosion elements such as copper, phosphorus, and chromium added improperly to the metal will create corrosion-resistant steel.

· Rolled steel: Like concrete, steel parts of any shape and size cannot be cast in place because steel requires very high temperatures to melt and be rolled into the required shape. Rolled steel parts, including steel columns, beams, channels, rectangular hollow sections, circular hollow sections, single angles, tees, double angles, and pre-fabricated steel building parts, are produced in steel mills and brought to the market