AISI 4140 Steel Bar

AISI 4140 Steel Bar, Steel Plate, Flats Supplier, Stockist and Exporter. AISI SAE 4140 alloy steel is a chromium molybdenum alloy steel specification widely used in general purpose high tensile steel for components, like axles, shafts, bolts, gears and other applications. Similar to alloy grade AISI 4130 chrome moly alloy steel but with a slightly higher carbon content. The higher carbon content of AISI 4140 steel gives greater strength and heat treatment capabilities in comparison to AISI / ASTM 4130 alloy steels, however it does have inferior weldability characteristics.

1. Supply Range for AISI alloy 4140 steel bar

4140 Steel Round Bar: diameter 8mm – 3000mm
4140 Steel Plate: thickness 10mm – 1500mm x width 200mm – 3000mm
4140 Steel Grade Square: 20mm – 500mm
Surface Finish: Black, Rough Machined, Turned or as per given requirements.

5. Forging

Preheat the steel carefully, heat to 1150 oC – 1200 oC maximum, hold until temperature is uniform throughout the section.
Do not forge below 850 oC.Following forging operation the work piece should be cooled as slowly as possible.

6. AISI 4140 Steel Grade Heat Treatment

Annealing
Heat ASTM 4140 steels to 800 oC – 850 oC, hold until temperature is uniform throughout the section and cool in furnace.

Normalizing
Heat steel alloy 4140 to 870 oC – 900 oC, hold until temperature is uniform throughout the section, soak for 10 – 15 minutes and cool in still air.

Tempering
Re-heat 4140 grade steel to 550 oC – 700 oC as required, hold until temperature is uniform throughout the section, soak for 1 hour per 25 mm of section, and cool in still air.

7. Hardening of AISI Alloy Steel 4140

AISI alloy 4140 steel bar, plate and square can be hardened by cold working, or heating and quenching.