High Carbon High Chromium Steel

Product Details:

High Carbon High Chromium Die Steel (HCHCR)Thread rolling dies, Hobs, Cold extrusion tools and dies, Punches, Draw plates and dies, Cutters, Measuring tools, Pressure casting moulds, Blanking, Reamer, Finishing rolls for tyre mills. This type of steel has high dimensional stability with added wear resistance coupled with excellent edge holding qualities. Cold-work tool steels include the high-carbon, high-chromium steels or group D steels. These steels are designated as group D steels and consist of D2, D3, D4, D5, and D7 steels. These steels contain 1.5 to 2.35% of carbon and 12% of chromium. Except type D3 steel, all the other group D steels include 1% Mo and are air hardened. Type D3 steel is oil-quenched; though small sections can be gas quenched after austenitization using vacuum. This makes tools made with type D3 steel brittle during hardening. Type D2 steel is the most commonly used steel among the group D steels.

The other designations of D5 tool steels are:

• ASTM A681
• FED QQ-T-570
• SAE J437
• SAE J438
• UNS

T30405Heat Treatment:

• D5 steels should be preheated very slowly up to 815°C (1500°F), then temperature should be increased to 1009°C (1850°F) and held for 20 to 45 minutes.
• Then they are air quenched.

Forging:

• Forging of D5 steels can be done at 1065°C (1950°F) down to 1750°F.
• Do not forge below 926°C (1700°F).

Annealing:

• Annealing of D5 steels should be done at 886°C (1627°F) followed by slow furnace cooling at 4°C (40°F) per hour or less.

Tempering:

• D5 steels can be tempered at 204°C (400°F) for achieving Rockwell C hardness of 61 and at 537°C (1000°F) for a Rockwell C hardness of 54.

Applications:

• Applications of D5 steels include thread rolling, blanking or forming dies operating at temperatures below 482°C (900°F).

Chemical composition:
Physical Properties:
Mechanical Properties:

Product Details:

D2 Tool SteelD2 steel is an air hardening, high-carbon, high-chromium tool steel. It has high wear and abrasion resistant properties. It is heat treatable and will offer a hardness in the range 55-62 HRC, and is machinable in the annealed condition. D2 steel shows little distortion on correct hardening. D2 steel’s high chromium content gives it mild corrosion resisting properties in the hardened condition.Cold-work tool steels include the high-carbon, high-chromium steels or group D steels. These steels are designated as group D steels and consist of D2, D3, D4, D5, and D7 steels. These steels contain 1.5 to 2.35% of carbon and 12% of chromium. Except type D3 steel, all the other group D steels include 1% Mo and are air hardened. Type D3 steel is oil-quenched.

Other designations that are equivalent to T5 tungsten tool steels include:

• DIN 1.2379
• NI KU
• B.S. BD 2
• ASTM A681
• FED QQ-T-570
• SAE J437
• SAE J438
• UNS T30402

Heat Treatment:

• D2 steels should be preheated very slowly to 815ºC (1500ºF) and then temperature can be increased to 1010ºC (1850ºF).
• They are then held at 1010ºC (1850ºF) for 20 to 45 minutes and air cooled (air quenched).

Forging:

• Forging of D2 steels can be done from 1065ºC (1950ºF) down to 954ºC (1750ºF).
• Do not forge below 926ºC (1700ºF).

Annealing:

• D2 is supplied in the annealed and machineable condition.
• Re-annealing will only be necessary if the steel has been forged or hardened by the toolmaker.
• To anneal, heat slowly and uniformly to 900°C.
• Soak for three to four hours and allow to cool in the furnace to room temperature.
• Re-heat to 800-1040°C and again soak for three to four hours.
• Allow to cool in the furnace to room temperature.

Tempering:

• D2 steels can be tempered at 204ºC (400ºF) for achieving Rockwell C hardness of 61 and at 537ºC (1000ºF) for a Rockwell C hardness of 54.

Martempering:

• Martempering is an alternative hardening procedure which may be used when suitable salt bath equipment is available.

Chemical composition:
Thermal Properties:
Physical Properties:
Mechanical Properties:

Product Details:

Cold-work tool steels which include D2, D3, D4, D5, and D7 steels are high-carbon, high-chromium steels. Apart from D3 steel all group D steels have 1% Mo and are air hardened. Type D3 steel is oil-quenched; though small sections can be gas quenched after austenitization using vacuum. As a result, tools made with type D3 steel tend to be brittle during hardening. Type D2 steel is the most commonly used steel among the group D steels. The D3 steels contain 1.5 to 2.35% of carbon and 12% of chromium.

 

Equivalent metals of D3 steel are:

• AFNOR Z 200 C 12
• DIN 1.2080
• UNI X 21O Cr 13 KU
• JIS SKD1
• B.S. BD 3
• ASTM A681
• FED QQ-T-570
• SAE J437
• SAE J438
• UNS T30403

Annealing:

• Annealing of D3 tool steel needs to be done in a controlled atmosphere furnace.
• D3 tool steels should be heated thoroughly to 871°C (1600°F) and cooled slowly at a rate of not more than -6°C (20°F) per hour, until the furnace is black.
• Then the material should be removed and air cooled.

Heat Treatment:

• D3 tool steel requires hardening and tempering to achieve maximum properties.
• For maximum accuracy, the parts of D3 tool steel should be stress relieved after roughing operations.
• Stress should be relieved at 648°C (1200°F) for one hour and cooled slowly.
• Tempering The D3 tool steel should be cooled to room temperature and should be tempered immediately.
• The parts should be placed in the tempering furnace and increased slowly to the desired tempering temperature.

Hardening:

• D3 tool steel should be heated properly since it is very sensitive to overheating and if not heated maximum hardness cannot be achieved.
• The work should be directly placed in a furnace preheated to 954°C (1750°F) and soaked for 20-25 minutes, plus 5 minutes per inch of thickness, and then oil-quenched to harden it.

Chemical composition:

The following table shows the thermal properties of D3 steels:

Physical properties of D3 tool steels are given below:

The mechanical properties of D3 steels are tabulated below:

Tempering for 1 hour per inch of thickness is required:

Product Details:

Characteristics1. With good hardenability and abrasion resistance.
2. With high oxidation resistance, good corrosion protection after quenching and polishing and little deformation through heat treatment.

Application:

• Used to manufacture different kinds of cold work moulds with high accuracy and long service life, cutting tools and measuring instruments.
• Such as complex-shaped piercing dies, threading screw plates, cold-extruding dies, cold-cutting scissors, precision measuring tools, etc.
• Cold work tool steel 1.2379, die steel 1.2379, DIN 1.2379 mould steel for die casting tools, forming dies, die inserts, hot shear blades.
• Pressure casting dies and metal extrusion tools for processing light metal alloys,tools for the manufacture of hollows, tools for the screws manufacture,nuts,rivets and bolts.

Soft Annealing:

• Heat to 840-880°C, cool slowly.
• This will produce a maximum Brinell hardness of 255. To secure uniform softness.

Stress Relieving:

• Stress relieving to remove machining stresses should be carried out by heating to 650-700°C, holding for one hour at heat, followed by air cooling.
• This operation is performed to reduce distortion during heat treatment.

Hardening:

• Harden from a temperature of 1000-1040°C followed by oil, warm bath (500-550°C, cooling bath or air.
• Hardness after quenching is 62-64 HRC.

Tempering:

• Tempering temperature: 150-550°C.

Chemical Composition:
Thermal Properties:
Quenching Process:
Tempering Process:
Forging: