12l14 steel

AISI 12L14 has great machinability and is suitable for case hardening and electroplating. It also is called automatic machine tool processing steel. It is used for machining automation and production line. It is mainly used for small force and strict requirements on size and finish tools, such as watch parts, automobiles, machine tools and etc. It has different names in different countries. People also call it as JIS SUM24L and DIN 1.0718 steel. 12L14 Steel round bar sheet plate properties and chemical composition as below.

1.0718 Steel Characteristics

  1. 12L14 steel can be machined with higher cutting speeds and larger depths of cut.
  2. Adding free-cutting elements to get great cutting performance.
  3. It is extremely easy to cut on a lathe, increasing tool life and productivity by 40%.
  4. Cutting and process are very easy. The processing efficiency gets better than general steel.

12L14 Steel Application

12L14 is used to manufacture tools which have requirements of high precision in size, high finish in surface, but low mechanical property, such as gears, shafts, bolts, valves, bushings, pins, fittings, spring seat and machine screw, plastic mold, surgical and dental procedures utensils, certain automobile parts, instruments, etc. Lead free-cutting steel has low contact fatigue, so it is not suitable for parts such as gears and bearings that are subjected to fatigue stress and load.

1.0718 Steel Physical Properties

Physical PropertiesMetric
Density7.87 g/cc

12L14 Steel Mechanical Properties

Hardness, Brinell163
Hardness, Knoop184
Hardness, Rockwell B84
Hardness, Vickers170
Tensile Strength, Ultimate540 MPa
Tensile Strength, Yield415 MPa
Elongation at Break10%
Reduction of Area35%
Modulus of Elasticity200 GPa
Bulk Modulus140 GPa
Poisson's Ratio0.29
Shear Modulus80 GPa

12L14 Steel Grade Equivalent Chart

StandardASTM A29/A29M-05EN 100087-1998JIS G4804-2008ISO 683/9:1988

12L14 Steel Chemical Composition

ASTM A29/A29M-05≤0.150.85-1.15≤0.04-0.090.26-0.35Max 0.100.15-0.35
EN 100087-1998≤0.140.90-1.30≤0.110.27-0.33≤0.050.20-0.35
JIS G4804-2008≤0.150.85-1.150.04-0.090.26-0.35≤0.100.10-0.35
ISO 683/9:1988≤0.140.90-1.30≤0.110.24-0.33≤0.050.15-0.35

12L14 Steel Round Bar Sheet Plate Heat Treatment


Heat to 890℃ – 920℃ hold until temperature is uniform throughout the section, and cool in furnace.


Pack, salt or gas carburize at 900℃ holding for sufficient time to develop the required case depth and carbon content, followed by a suitable refining/hardening and tempering cycle to optimize case and core properties.

Core Refine

Slow cool from carburizing temperature and re-heat to 880℃ – 900℃, hold until temperature is uniform throughout the section and quench as required in oil, water.

Case Hardening

Following core refining, re-heat to 760℃ – 790℃, hold until temperature is uniform throughout the section and quench in water. Temper immediately while still hand warm.

Tempering – After Carburising, Core Refining and Case Hardening

Re-heat 12L14 steel to 120℃ – 230℃, hold until temperature is uniform throughout the section, soak for 1 hour per 25 mm of section and cool in still air.NB. Tempering will improve the toughness of the case with only slight reduction in case hardness. It will also reduce it’s susceptibility to grinding cracks.

Songshun Steel Factory


Heat to 900℃ – 940℃ hold until temperature is uniform throughout the section, soak for 10 – 15 minutes. Cool in still air.

Stress Relieving

Heat to 500℃ – 700℃ hold until temperature is uniform throughout the section, soak for 1 hour per 25mm of the section, and cool in still air.

Notes on Heat Treatment

Heating temperatures, rate of heating, cooling and soaking times will vary due to factors such as work piece size/shape, also furnace type employed, quenching medium and work piece transfer facilities etc. Please consult your heat treater for best results.


It is a premium free cutting steel grade suitable for all types of high production and repetition machining.


12L14 steel is not recommended for welding due to its lead content. It is a health hazard.

We have our own cutting and processing equipment. Specifications can be cut and customized according to your requirements.

We are a professional special steel stockist and supplier with a high-quality stand for many years. As a professional 12L14 steel supplier, please contacts us for any request for it. Songshun Steel always with you.