AISI 12L14 Steel Round Bar Sheet Plate, JIS SUM24L, DIN 1.0718

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.

12L14 Steel Round Bar Sheet Plate Supply Range
Round BarDia:1-2000mm; Length: Can be customized
We can supply any lenth based on the customer's requirement.
Black Surface/Bright Surface /Grinded/Peeled/Turned
Sheet/Plate/Slab Can be customizedBlack Surface/Bright Surface /Grinded/Peeled/Turned

12L14 Steel Grade Equivalent Chart

Country USA Germany/UK/France JAPAN ISO
Standard ASTM A29/A29M-05 EN 100087-1998 JIS G4804-2008 ISO 683/9:1988
Grades 12L14 11SMnPb30(1.0718) SUM24L 11SMnPb28

12L14 Steel Chemical Composition

STAND C(%) Mn(%) P(%) S(%) Si(%) Pb(%)
ASTM A29/A29M-05 ≤0.15 0.85-1.15 ≤0.04-0.09 0.26-0.35 Max 0.10 0.15-0.35
EN 100087-1998 ≤0.14 0.90-1.30 ≤0.11 0.27-0.33 ≤0.05 0.20-0.35
JIS G4804-2008 ≤0.15 0.85-1.15 0.04-0.09 0.26-0.35 ≤0.10 0.10-0.35
ISO 683/9:1988 ≤0.14 0.90-1.30 ≤0.11 0.24-0.33 ≤0.05 0.15-0.35

1.0718 Steel Physical Properties

Physical Properties Metric
Density 7.87 g/cc

12L14 Steel Mechanical Properties

Properties Metric
Hardness, Brinell 163
Hardness, Knoop 184
Hardness, Rockwell B 84
Hardness, Vickers 170
Tensile Strength, Ultimate 540 MPa
Tensile Strength, Yield 415 MPa
Elongation at Break 10%
Reduction of Area 35%
Modulus of Elasticity 200 GPa
Bulk Modulus 140 GPa
Poisson's Ratio 0.29
Machinability 160%
Shear Modulus 80 GPa

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 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 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 Refinea

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.


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.


12L14 Steel Round Bar Sheet Plate Supply

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 AISI 12L14 Steel Round Bar Sheet Plate.

supplier, please contacts us for any request for it. Songshun Steel always with you.

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