itself carburizing steel is a process based on the chemical and thermal processing.It consists in carrying out a diffusion saturation of the surface of said material a sufficient amount of carbon when heated to a certain environment.
Cementation steel.The purpose of this action
main objective of this process is to conduct enrichment of the top layer of machine parts and elements necessary amount of carbon, the percentage of which in this case may be 0.8-1.1%.As a result of such an operation is obtained after quenching of the high level of hardness of the material, while its plastic core is maintained.This important feature of this process.
Species
According to the degree of strength of the core of education is divided into three main groups of the processed material:
- With neuprochnyaemoy core.This group includes such brands cemented carbon steel, like 10, 15, 20. Use them in detail with the small size and malootvetstvennymi functions.In this case, a layer of cemented quenching occurs when implementing the transformation of austenite to ferrite-perlite mixture.
- With core strengthens the weak.The group includes chromium low alloy steels such brands as 15X, 20X.Here holding additional doping using small additions of vanadium produces a fine grain, thus improving ductility and toughness of the material.
- hardenable with strong core.Steels of this group are used in the manufacture of parts, which have a large cross section or complex configuration and are affected by major shocks or are exposed to considerable stress variables.They carried out the introduction of nickel (12Kh2N4A, 12HNZA, 20HN).Due to the scarcity of this material is sometimes carried out its replacement by manganese, with a small amount of input used vanadium or titanium for crushing grain.
Basically carburizing steel is used to form a high percentage of the surface hardness of parts as well as to achieve high durability, which is created by applying heat treatment after the process.
What are the details of this transaction are subject to
carburizing steel is used for the following products:
- gears;
- "fingers";
- shafts;
- axes;
- leverage;
- "worms";
- bearing parts (large-sized rings and clips), and others.
grouting methods
If there are several kinds of said material, then each of them will apply its own method in this process.Generally, cemented steel may be generated in different conditions and environments, as well as a mandatory temperature of 850 to 950 degrees Celsius.So share several methods of action:
1. cementation process occurring in the solid carburizer.In this case the possible use of organic materials (animal bones, wood, etc.) and inorganic (coke) in conjunction with various activators.Enrichment of carbon will occur during the chemical reaction of oxidation.The use of activators in this case contributes to better and faster the reaction.This method is particularly useful for achieving greater depths carburizing.It is effective in the manufacture of steel products unit shipments.However, this process is very time-consuming, it entails a great expenditure of energy, time and energy.
2. cementation process occurring under the influence of gases.This method made use of enriched gas (natural, trunk, etc.) Or category of inert (nitrogen).It all depends on the individual.Besides carburising steel-based gas generated from a small percentage of aliphatic saturated hydrocarbons as propane or alkanes.Most often, this method is used in large-scale production, but is very costly in terms of money.A similar method is used in thermal production.In the hot rotortnuyu introduced into the furnace a mixture of organic high molecular compounds (e.g., turpentine, ethyl alcohol, etc.), which, in turn, have the ability to collapse under the influence of catalysts (nickel).
3. The process liquid cementation.It is used in cyanide and bestsianidnyh baths.Each of these environments is characterized by its own characteristics, advantages and disadvantages.For example, a cyanide bath is not classified as harmless.They are usually classified as dangerous for the media, not only the environment but also for humans.Therefore, when working with such material should try to comply with all the prescribed precautions to avoid unfavorable consequences.But the method based on bestsianidnoy bath is not recommended to apply due to the fact that it leads to irreversible contamination of the environment and dealing massive damage.These methods if put into practice, then only for small depths of carburization.
Heat cemented products
This process is also quite important stage machining.Even after cementation does not have a high percentage of durability and reliability.Therefore, the final step in this case is the work hardening and tempering.Quenching process has a number of features and properties.The entire process takes place under the influence of cementation grain growth and its returns over the cross section is unequal and consumed unevenly.Therefore, the recovered quenching stages, each of which occurs in certain temperature conditions.
Conclusion After reading the above, we can say that the organization of this process in the manufacture of steel products is very important.This action will significantly strengthen the surface layer of the part.When owning certain skills in this area and the necessary materials and equipment can be carried out carburizing steel at home.
