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rTool steel grades.
Tool steel - alloy or carbon steel intended for the manufacture of cutting
and measuring tools, cold and hot deformation dies, machine parts
experiencing increased wear at moderate dynamic loads.
Alloy steel - steel into which, during alloying, special elements are
introduced in certain quantities to ensure the required properties. Such
elements are called alloying elements. They can increase the strength and
corrosion resistance of steel and reduce the risk of brittle fracture.
Steel alloying can be carried out at various stages of metal production and
consists in the introduction of alloying elements into the melt or charge.
In the process of alloying the steel, the introduced elements can form
special chemical compounds with the steel base. Such intermetallic, carbide
and nitride elements have high hardness and strength, chemical resistance,
heat resistance, etc. The uniform distribution over the entire volume of the
solid solution and a sufficient amount of these elements in the steel give
the metal the necessary properties when alloying the steel.
The following chemical elements are used for alloying steel: manganese (Mn)
- G; silicon (Si) - C; chromium (Cr) - X; nickel (Ni) - H; copper (Cu) - D;
nitrogen (N) - A; vanadium (V) - F; niobium (Nb) - B; tungsten (W) - B;
selenium (Se) - E; cobalt (Co) - K; beryllium (Be) - L; molybdenum (Mo) - M;
boron (B) - P; titanium (Ti) - T; aluminum (Al) - Yu.
Pure metal elements are usually not used when alloying steel. Ferroalloys
(iron alloys) and master alloys (auxiliary alloys) are most often used for
alloying steel. This is more cost-effective and avoids a number of
technological difficulties in the process of alloying steel.
CLASSIFICATION OF ALLOY STEELS
By the number of alloying elements:
highly alloyed - the total weight of alloying elements is more than 10%;
medium alloyed - the total mass of alloying elements is more than 2.5-10%;
low-alloyed - the total weight of alloying elements is up to 2.5%.
By appointment:
I - for the manufacture of tools used for processing metals and other
materials in a cold state;
II - for the manufacture of tools used for processing metals by pressure at
temperatures above 300 ° C.
By the method of further processing:
a - hot-rolled and forged metal products for hot forming and cold drawing
without control of structural characteristics;
b - hot rolled and forged metal products for cold machining with a full
scope of tests. .