Otai 4340 steel material
4340. Material for heavy-machinery shafts, transmission parts, gears and crankshaft fasteners. Carbon composition: 0.370–0.430 %; Chromium composition: 0.700–0.900 %.
Specifications
| Attribute | Value | Conditions | Source |
|---|---|---|---|
| Carbon composition | 0.370–0.430 % | Supplier published chemical-composition percentage; exact 4340 table, percentage basis not separately stated; not a batch assay or mill certificate | Otai 4340 original grade composition and application page |
| Chromium composition | 0.700–0.900 % | Supplier published chemical-composition percentage; exact 4340 table, percentage basis not separately stated; not a batch assay or mill certificate | Otai 4340 original grade composition and application page |
| Nickel composition | 1.65–2.00 % | Supplier published chemical-composition percentage; exact 4340 table, percentage basis not separately stated; not a batch assay or mill certificate | Otai 4340 original grade composition and application page |
| Molybdenum composition | 0.200–0.300 % | Supplier published chemical-composition percentage; exact 4340 table, percentage basis not separately stated; not a batch assay or mill certificate | Otai 4340 original grade composition and application page |
Sources and updates
Scope of this page: One named steel grade offering; AISI/DIN/JIS aliases, round/flat/plate stock, dimensions, surface finish and heat-treatment options are not extra products. Chemical composition is a supplier reference, not independently assayed or a guarantee of conformance to an unreviewed standard edition. No generic heat-treatment recipe, unconditioned hardness, service-temperature limit or safety approval adopted. The supplier is identified without claiming original trademark ownership or an endorsed distribution relationship.
Otai 4340 original grade composition and application page
Original publication · Otai
Source accessed: 27 October 2026
Content updated 27 October 2026. Source dates describe the documents or the recorded access to them.
How information is documented