SAE 12L14 Free-Cutting Steel

The Pinnacle of Machining Speed.

For some manufacturing processes, 'fast' isn't fast enough. When production runs into the millions and cycle times are measured in fractions of a second, a new level of performance is required. SAE 12L14 is that next level. By combining a precise chemistry of Sulphur, Phosphorus, and Lead, it achieves the highest machinability rating possible, creating a steel that flows through machinery not like a solid, but like a fluid, enabling speeds and finishes that other grades simply cannot touch.

The Chemistry of Maximum Velocity

The Ultimate Machinability

Possesses the highest machinability rating of any common steel, designed for maximum removal rates.

Perfect Chip Formation

The chemistry is engineered to produce small, fine, and brittle chips that break away cleanly and do not interfere with tooling.

Exceptional Surface Finish

The clean cutting action allows for a smooth, bright, and highly accurate surface finish directly from the machine.

Maximum Tool Longevity

The self-lubricating properties of lead drastically reduce friction and heat, leading to significantly longer tool life.

Technical Specifications

Chemical Composition

Element Content (%)
Carbon (C) 0.15 Max
Manganese (Mn) 0.85 - 1.15
Sulphur (S) 0.26 - 0.35
Lead (Pb) 0.15 - 0.35
Phosphorus (P) 0.04 - 0.09

Mechanical Properties

Machinability Rating Considered the benchmark for machinability (100% against itself, approx. 170% vs B1112 steel).
Strength & Hardness This grade is not selected for its strength. It is a soft, low-strength steel designed purely for ease of cutting.

Common Applications

High-volume automatic screw machine products
Screw Machine Products
Bushings and couplings produced at high speed
Bushings & Couplings
Small shafts and pins for electronics and appliances
Pins & Small Shafts

Equivalent International Grades

Standard Grade
BS EN1AL (Leaded)
DIN / W-Nr. 9SMnPb28 / 1.0718

Similar & Alternative Grades:

EN1A (Non-Leaded) EN8M

Frequently Asked Questions about SAE 12L14

What makes 12L14 so easy to machine?

It's a powerful combination of three elements. Sulphur and Phosphorus make the steel brittle, so metal chips break off in small, clean pieces instead of forming long, stringy curls. The addition of Lead (L) acts as a built-in, microscopic lubricant at the tool's cutting edge, drastically reducing friction and heat.

What are the limitations of 12L14?

Its exceptional machinability comes with significant trade-offs. The same elements that make it easy to cut also make it brittle, with low strength and ductility. It is completely unsuitable for welding, forming, or any application that requires structural strength or toughness. It is purely a machining-grade steel.

Is 12L14 the same as EN1AL?

They are very similar in purpose and both are leaded free-cutting steels. However, 12L14 is generally considered to have a higher machinability rating due to its additional Phosphorus content, making it the top choice for the absolute fastest production speeds.


Redefine Your Production Limits

Your machines are capable of incredible speeds, but they are often limited by the material they are cutting. The Marbrite Standard for SAE 12L14 is our commitment to providing the ultimate free-cutting steel. We deliver **12L14 bright bars** with a perfectly controlled chemistry, designed to break the barriers of traditional machining speeds. Unleash the true velocity of your production and achieve a new standard of efficiency.