Steel 4620

Aging Procedure

Not applicable to this alloy.

Annealing Procedure

Anneal at 1600 F followed by slow furnace cooling.

Cold Workability

Cold working of this alloy in the annealed condition can be readily accomplished with conventional methods.

Forgeability

Forge at 2250 F maximum down to 1800 F.

Formability

Formability is good in the annealed condition.

Hardening Procedure

This alloy hardens by cold working or heat treatment. See "Heat Treatment" and "Tempering".

Heat Treatability

Heat to 1550 F for sufficient time to allow thorough heating and then oil quench. It is desirable to normalize the alloy at 1700 F followed by air cool, before doing the heat treatment and oil quench.

Hot Workability

The alloy may be hot worked at 1900 F down to 1500 F.

Machinability

Machinability is good, especially in the annealed or normalized conditions. In the hardened tempers it becomes increasingly more difficult to machine.

Principle Design Features

AISI 4620 is a nickel, molybdenum, manganese low alloy steel often used for carburized parts. It has a good combination of strength and toughness and can be heat treated to high strength levels.

Tempering Procedure

Temper at 400 F to 1300 f depending upon strength/hardness desired. Tempering is done following the heat treatment and oil quench. Tempering at 600 F gives a strength of approximately 210 ksi while tempering at 1000 F gives approximately 135 ksi.

Weldability

4620 may be welded by conventional means prior to heat treatment or carburization.