BILBAINA DE TRATAMIENTOS
The hardening steels are a group of steel low carbon content between 0.05% and 0.25%, intended for the manufacture of parts which must combine a high surface hardness and good toughness and high impact resistance.
This combination of properties is very important for those parts, like gears, which should have a very hard surface to resist wear and change the core of the teeth must be very tough to can take the knocks eligible because startups , sudden stops, etc.. Machine suffering.
Depending on the alloying elements, these steels can be classified into three groups:
This group includes the steels containing only between 0.10% and 0.25% C, less than 0.35% silicon If, between 0.50% and 070% Mn and small percentages of impurities such as P, S, O etc.. These steels are quenched with water, which results in surface hardness of 60HRC and the core resistance 80Kg/mm2. Are used for the manufacture of small parts and simple ways in which it is unlikely that problems arise and deformations in the strength and toughness of the core are not of great interest.
This group of steels in which the sum of the percentages of the alloying element s such as Cr, Ni, Mo and Mn does not exceed 3%. These steels are Cr-Mo, Ni-Mo and Ni-Cr-Mo. In this group, high alloy steels are quenched in oil and tempered low alloy with water. The piece size can also dial the kind of mettle, and thus can occur in the case of small parts, these are quenched in oil while in the case of these larger pieces are quenched in water. They are used to manufacture parts of medium and small sizes, you should beware strains and interests in toughness and strength in the core of between 70 and 90Kg/mm2.
This group includes steels containing alloy elements higher than 3% and in which the carbon content is usually less than 0.2%. Among those found Ni steels and Cr-Ni. These steels are quenched in oil, which results in resistance of the core 90 to 150Kg/mm2. Are used for parts of any size and responsible for the good toughness and a high strength is required of the core and the non-sensitive strains also allowed to temper.