Size Range

1. Round bar:

Surface condition Diameter Length

Black 80-1200mm Random

Turned 120-800mm Random

2. Flat Bar:

Surface condition Height Width Length

Black 50-600mm 1600mm max Random

Turned 80-600mm 1200mm max Random

HEAT TREATMENT

Annealing: AISI 4320 might be processed through case hardening and subsequent heat treatment operations without the need for annealing. Its microstructure as forged will be suitable for such treatments, but in the case of small sections where a very fine structure may result from forging, a normalizing treatment would be recommended prior to further heat treatment.

Normalizing: AISI 4320 is normalized at a temperature of around 1700ºF (925ºC.) Air cooling follows heat treatment. It should be noted that experience alone will determine the normalizing temperature for a specific part following given forging conditions.

Hardening: AISI 4320 should be austenitized following carburizing at a temperature in the region of 1525 -1550ºF (830 – 845ºC) followed by oil quenching.

Tempering: The alloy will be tempered at a temperature that will most probably be based on past experience, according to required mechanical properties.

Machinability: The alloy is readily machinable in the forged – depending upon section size – condition or following normalizing. Finish machining following harden and temper is applicable.

Weldability: AISI 4320 is readily weldable by all normal methods. The alloy should however be welded in the as-forged or normalized conditions only, and not following harden and temper.

Dimension Tolerance Standard: DIN 7527.

Ultrasonic Test: SEP 1921 3C/c or specific FBH eq.

Mill′s test certificate:

EN 10204/3.1 with all relevant data reg. chem. composition, mech. properties and results of testing.