20 questions about steel
1. What is steel?
Steel is a metallic alloy made primarily from iron and carbon, with small amounts of other elements such as manganese, nickel and boron. The properties of steel can be modified through various heat treatment processes and the addition of different alloying elements. Steel is known for its strength, durability and versatility, and is used in a wide range of applications, including; construction, transportation, machinery and appliances.
2. How is steel made step by step?
The raw material for steel is iron ore and/or recycled steel scrap. The molten iron, which is produced in a blast furnace (BF) or electric arc furnace (EAF), is purified in a converter. The required alloying elements are added in the secondary metallurgy. Finally, the steel is cast into slabs, which are then rolled and heat treated. Before delivery, the material can be leveled, blasted, galvanized, metal and color coated.
3. What is the density of steel?
The density of steel is approx. 7.85 g/cm3 or 490 lb/ft3.
4. How do the material properties change after forming?
When deforming a piece of steel, the resistance against further deformation increases. This is strain or deformation hardening. Yield strength and hardness will increase, while some ductility is lost.
5. What is the tensile test for steel?
Tensile testing is one of the best-known tests for steel and can be defined by standard EN 10002. Controlled displacement is applied on a standard specimen. The relation between load and elongation is recorded and used to determine a number of material properties, e.g. yield strength and tensile strength.
6. What is the yield strength and the tensile strength of steel?
Yield strength is the maximum stress level that steel can withstand before plastic deformation occurs. Above this stress level, steel will no longer return to its initial dimensions or shape. Ultimate tensile strength is the stress level where the load is at a maximum during tensile testing and using the original cross section area.
7. What is the stress-strain curve for steel?
The stress-strain curve for steel shows the relationship between applied load and elongation during tensile testing. It is used to determine mechanical properties of the material, including modulus of elasticity, yield strength, and ultimate tensile strength. The load values are transformed into stress values and the elongation is transformed into strain, resulting in a curve that provides important information on how the material behaves under different loading conditions.