ASTM D2 Tool Steel | DIN1.2379 | SKD11

ASTM D2 Tool Steel | DIN1.2379 | SKD11

Cold-work tool steels include the high-carbon, high-chromium steels or group D steels. ASTM D2 plastic mold tool steel Manufacturer and Exporter, supplied with round, square, and flat. ASTM D2 is a high-carbon, high-chromium tool steel alloyed with molybdenum and vanadium as per ASTM A 681 standard. It is the most commonly used steel among the group D steels. It has high abrasive wear resistance, high compressive strength, good through-hardening properties, high stability in hardening and good resistance to tempering-back. ASTM D2 is often supplied in annealed condition.

Designation by Standards

Chemical Composition (%)

Physical Properties

The physical properties of ASTM D2 tool steels are outlined in the following table.

Mechanical Properties

The mechanical properties of D2 steels are tabulated below:

Fabrication and Heat Treatment

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). Heat slowly and uniformly to 700°C then more rapidly to 900/1040°C. Do not continue to forge D2 below 925°C. Reheat as often as necessary to maintain proper forging temperature. After forging cool slowly. This is not an annealing process. After the forging is cold, it must be annealed as described below.

Annealing

Annealing of D2 steels should be done at 871 to 898ºC (1600 to 1650ºF) followed by slow furnace cooling at 4.4ºC (40ºF) per hour or less.

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.

Applications

D2 tool steels are used for long run tooling applications, where wear resistance is important, such as blanking or forming dies and thread rolling dies.