AISI A2 Steel Round Bar Sheet Plate, DIN 1.2363, JIS SKD12

AISI A2 Steel Round Bar Sheet Plate, DIN 1.2363, JIS SKD12


A2 steel is called DIN 1.2363 and JIS SKD12 steel. 1.2363 steel is a cold work mold steel that is improved on the basis of SKD11 steel. The toughness of 1.2363 steel is twice that of SKD11. The retained austenite is almost all decomposed under the conventional heat treatment conditions. The toughness of 1.2363 steel is great in the cold work mold steel. There are no cracks of industrial products due to be made of A2 steel round bar sheet plate material. A2 steel properties and A2 steel heat treat as below.

1.2363 Steel Characteristics

  1. High toughness. The products that were made of A2 steel material almost no cracking or cracking occurs during the use.
  2. The machinability is also better than SKD11 steel. Using 1.2363 steel can increase the service life of the mold and get higher production efficiency.
  3. High quench hardening ability. so it can efficiently avoid the defects which be caused by insufficient hardness during vacuum heat treatment.
  4. The surface hardness is higher after surface hardening treatment. It can efficiently improve the performance of the mold.

A2 Steel Application

steel mold

The application is decided by A2 steel chemical composition and properties. It has high hardness and toughness. The application as below:

  1. Precision stamping die.
  2. Precision blanking dies for wire cutting and stamping die for various purposes.
  3. Cold forging, deep drawing and boring molds.
  4. High-speed punching punch, stainless steel plate punch.
  5. shear and slitter blades.

A2 Steel Physical Properties

Temperature68°F (20°C)375°F (200°C)750°F (400°C)
Modulus of elasticity
Coefficient of thermal expansion
per °F from 68°F6.5*10-6
per °F from 68°F11.6*10-6

A2 Steel Mechanical Properties

Hardness, Rockwell C (as air-hardened (63-65 HRC average), 60-62 HRC at 205°C, 59-61 HRC at 260°C, 58-60 HRC at 315°C, 57-59 HRC at 370°C and 425°C and 480°C, 56-58 HRC at 540°C, 50-52 HRC at 595°C, 42-44 HRC at 650°C)6464
Bulk modulus(typical for steels)140 GPa20300 ksi
Machinability(based on carbon tool steel)65%65%
Shear modulus78.0 GPa11300 ksi
Poisson’s ratio0.27-0.300.27-0.30
Elastic modulus190-210 GPa27557-30457 ksi

A2 Steel Grade Equivalent Chart

StandardASTM A681-08
Alloy Tool Steel
EN ISO 4957-1999
Tool Steel
JIS G4404-2006
Tool Steel
ISO 4957: 1999
Tool Steel

A2 Steel Chemical Composition

ASTM A681-080.95-1.050.40-1.00Max 0.030Max 0.0300.10-0.504.75-5.500.15-0.500.90-1.40
EN ISO 4957-19990.95-1.050.40-0.80Max 0.030Max 0.0300.10-0.404.80-5.500.15-0.350.90-1.20
JIS G4404-20060.95-1.050.40-0.80Max 0.030Max 0.0300.10-0.404.80-5.500.15-0.350.90-1.20
ISO 4957: 19990.95-1.050.40-0.80Max 0.030Max 0.0300.10-0.404.80-5.500.15-0.350.90-1.20

1.2363 Steel Forging

Heating A2 steel for forging must be done slowly and uniformly. Heat the steel 1.2363 slowly to 700°C then more rapidly to 1050-1100°C. Avoid working below 899°C(1650°F). Reheat AISI A2 steels as often as necessary to maintain proper forging temperature. After forging cool very slowly in lime, mica, dry ashes or furnace. DIN 1.2363 steel should always be annealed after forging.

a2 steel heat treat

A2 Steel Round Bar Sheet Plate Heat Treatment

Stress Relieving

After heavy grinding or machine, it is advisable to stress relieve tool steel 1.2363 to reduce the danger of cracking or distortion during subsequent heat treatments. Heat slowly to 670-700°C, soak for a minimum of two hours per 25mm of the section then cool down in the furnace.


1.2363 tool steels are annealed at 857°C (1575°F) and then cooled slowly in the furnace at a rate of 4°C (40°F) per hour or less.


Preheating temperature: 1200–1380°F (650–750°C). Austenitizing temperature: 1700 –1780°F (925–970°C) but usually 1720–1760°F (940–960°C).


1.2363 tool steels are heat treated at temperatures ranging from 177°C (350°F) for Rockwell C 62 to 538°C (1000°F) for Rockwell C 56 and then tempered.


Martempering bath or fluidized bed at 360–430°F (180–220°C) or 840–1020°F (450–550°C) then cool in the air.

Circulating air or atmosphere.

Vacuum furnace with an overpressure of gas at cooling.

Oil (only for small and uncomplicated tools).


Nitriding will give a hard diffused surface layer which is very resistant to wear and erosion, and also increases corrosion resistance. Nitriding Din 1.2363 steels in ammonia gas at a temperature of 975°F (525°C) gives an A2 steel surface hardness of approx.

h11 steel round bar


DIN 1.2363 tool steels are alloy steels and hence they are capable of being welded. However, welding of 1.2363 tool steels is not much preferred due to the risk of crack formation. The following guidelines can be followed during the welding of 1.2363 steels:

A. Welding in order to harden the soft annealed 1.2363 tool steel

  1. Heat to austenitizing temperature
  2. Cool to approx. 500°C (932°F)
  3. Weld at approx. 500°C (932°F)
  4. Cool to approx. 100°C (212°F)
  5. Hard facing electrode

B. Repair welding of 1.2363 tool steels in hardened and tempered condition

  1. Preheat to the tempering temperature (min. 200°C) (392°F)
  2. Weld at the tempering temperature
  3. Heat immediately to tempering temperature, but max. 300°C (572°F). Soak the steels for 3 hours
  4. Cool in the air to approx. 80°C (176°F)
  5. Heat to tempering temperature. Soak for 2 hours
  6. Hard facing electrode

C. Welding of soft annealed A2 tool steel

  1. Preheat to 300-500°C (572-932°F)
  2. Weld at 300-500°C (572-932°F)
  3. Stress relieve immediately.
  4. Cr-Mo alloy electrode for welding structural steel

Heat Treatment

A2 tool steels are heated slowly to 788°C (1450°F) and this is followed by increasing the temperature to 954°C (1750°F). 1.2363 tool steels are further held at 954°C (1750°F) for 30 to 45 minutes and finally removed from the furnace and cooled.


1.2363 tool steels have medium machinability, about 85% that of the W group of tool steels which are rated at 100% for a baseline.

A2 Tool Steel Round Bar Sheet Plate Supply

Round Bar

Specification: Dia Max 800mm; Length: Max 6m
Surface: Black, Peeled, Machined(Turned), Polished(Grounded)


Specification: thickness: Max 800mm; width: Max 810mm; length: 3-5m
Surface: Black, Peeled, Machined, Polished(Ground,Grinded, Milled)


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 A2 steel supplier, please contacts us for any request of A2/1.2363 steels materials. Songshun Steel always with you.