Alloy steels are simply steels that have been alloyed with other elements such as manganese, molybdenum, vanadium, silicon, boron, nickel and chromium.

Technically speaking, all steels are alloys, as steel is a combination of Iron (FE) and Carbon. ‘Alloy steels’, however, are those that have additional elements alloyed with them, in addition to the Carbon.

The alloying is done to achieve certain properties within the steel, such as increased hardness, hot hardness, strength, toughness, wear resistance, corrosion resistance and hardenability.

Quenching and tempering is a two-step process in which the metal is first heated to extreme temperatures and quickly cooled in water to harden the steel (known as quenching). The metal is clamped securely to avoid warping. The steel is then tempered, in order to achieve the desired properties.

Quenched and tempered steel is characterised by good ductility and strength, and an extremely fine-grained microstructure.

4140 Alloy Steel

4140 is 1% chromium-molybdenum, medium hardenability, general purpose high tensile steel.

4130 Alloy steel

AISI 4130 alloy Steel is a high quality Quenched and Tempered Alloy Structural steel,  Oil Quenched & Tempered Hardenss is 28-34 HRc. AISI 4130 steel Annealing delivery 4130 With a lower carbon content range, So the 4130 alloy steel have better weldability than AISI 4140 Alloy steel.

4340 Alloy Steel

4340 is a nickel-chromium-molybdenum alloy steel known for its toughness and its ability to attain high strengths in the heat-treated condition. It has very good fatigue resistance.