Carbon & alloy steel
AISI 12L14
Manufacturer or standards-body identification; product values do not apply to every form or condition.
Identity / state reference
What distinguishes this material
Nucor lists 12L14 as a separate cold-finished bar grade. The leaded designation must not be replaced by an unqualified non-leaded counterpart.
- Designation in this reference
- SAE 12L14
- Forms covered by the sources
- Nucor cold-finished bars; consult the grade/shape listing.
- States to distinguish or confirm
- Delivery hardness and cold-working history must be specified.
- Temperature and exposure
- No universal service-temperature limit or room-temperature property set is assigned. Use the cited product document and the purchase certificate.
Property evidence for a stated condition
No condition-specific numerical table is reproduced here
The linked sources establish the identity and the stated product/state scope. Obtain the row for your actual form, section, treatment and test conditions before adopting strength, hardness or a thermal limit.
Resolve these conditions next
- What product standard, edition and complete grade are on the material certificate?
- What product form, section size and delivery/heat-treatment condition will be machined?
For machining, take the exact grade, supplied condition and measured hardness where applicable into the tool maker’s application data. A generic material-family speed is not a substitute for an operation and tool-specific recommendation.
Sources and what they establish
Reviewed 23 October 2026. A source’s publication date and the review date are different. The scope below identifies the fields checked.
Nucor cold-finished bar product programme
Grade-specific round, hexagon, square and flat listings; distinguishes 1144 SR and 4140 annealed listings.
Nucor cold-finished bar product programme ↗Source identity, a named product example and a supplied-batch certificate are different evidence. Cross-standard similarity does not approve substitution.
Corrections from the previous article
- Remove the old universal machinability percentage and any EN/JIS equality not supported by the actual purchase specification.
- Withdraw the legacy generic hardness (130 HB) and tensile-strength (540 MPa (78 ksi)) pair: the old page does not establish a matching product, heat treatment, section and test source.
- Remove the unsupported cutting-speed table and machinability percentage; select tooling only after the actual material condition is known.