Production and Uses of 4130 Alloy Steel

Production and Uses of 4130 Alloy Steel
Page content


4130 alloy steel is one of the most important steel alloys. Basically, this alloy is better for heat treatment compared to others. High toughness of this alloy makes it different from others. Due to its toughness, it is used in aircraft for manufacturing leading gears and other parts. Its strength can be increased up to a certain extent by heat treatment. It is a low alloy material and best for welding purpose and widely used in the resistance welding process. It has great features so that it is best for machining process such as annealing and normalizing.

Composition of 4130 alloy

This is an alloy of steel that contains alloying material mainly chromium and molybdenum. Some other elements are also present in this alloy such as carbon, phosphorous, silicon, and sulfur. In facts, the value 30 represents that it contains 0.30 % carbon in it. The percentage of chromium and the percentage of molybdenum are 1.06 % and 0.36% in this alloy steel, respectively. Due to presence of chromium and molybdenum, it contains both types of alloy properties. However, chromium- molybdenum steel has not as good in a combination of strength and ductility as nickel, chrome-nickel and chrome-vanadium steels, but it is quite easy to roll and draw into tubes so that to fabricate, and to weld. This is why it is very popular for manufacturing airplane structural parts.

Effect of different properties in steel due to chromium and molybdenum

Effect of chromium component

  • The presence of chromium increases the resistance of a material towards corrosion. Steel becomes more resistive to corrosion due to presence of chromium.

  • Chromium content increases the hardenability of steel. Chromium improves the hardenability of any material.

  • Chromium element increases the resistance to wear and abrasion of the steel.

It improves the strength of steel when this alloy steel is subjected to heat treatment. At high temperature, the strength of the steel becomes very high due to chromium.

Effect of Molybdenum component

  • When a part is subjected to a constant stress at high temperature for a long period of time, it undergoes a slow and permanent deformation called creep. The component of molybdenum increases the creep strength of steel.

  • It increases the red hardness of the alloy steel.

  • Similar to chromium, it also improves the hardenability of steel.

The addition of molybdenum component forms the abrasion-resisting particles. These particles are responsible for resisting wear and abrasion.

Uses of 4130 Alloy

  • This Alloy is used for manufacturing ball and roller bearings.

  • This alloy is also good for manufacturing gears due to their heat treatment property.

  • It is used for rock-crushing machinery and automotive parts.

  • It is used for manufacturing structural parts of aircraft.

  • The main use of this alloy is in the field of resistance welding.

  • It is used for cutter tools such as drills, taps, milling cutters, etc.


4130 steel alloy is famous for its strength property when it is used for heat treatment. The importance of this steel is in aircraft manufacturing companies and welding purpose. It has features of both chromium and molybdenum steel alloys.


Image: aircraft Based on 4130 alloy steel