What is a Recarburizer?
Recarburizer is a kind of used to increase the carbon content of ferroalloy products, carburant can be divided into graphite recarburizer JiaoZeng carbon agent, oil and coal quality recarburizer foundry recarburizer is a designed for casting production recarburizer products, using electric furnace in the casting process by only join metal burden is not enough to save the carbon content in the molten iron, in the case of the carbon content of erosion, will need to use the foundry recarburizer to ensure to achieve production standards of carbon content in molten iron, thus casting using recarburizer plays an important part in casting!
Recarburizer is widely used in steelmaking and casting
Used in casting foundry carburant can effectively generate and promote the graphite core, add a certain proportion in liquid iron casting with carburant, some were dissolved in molten iron, but there are still a part of not melting casting using recarburizer would be in the form of graphite, carbon and with granular liquid iron in the water, there is no lack of among them some of the larger foundry recarburizer particles, the foundry not melt when electricity recarburizer will firmly adsorbed in the middle of the smelting furnace of the furnace wall, but if the power is, these are not melting foundry carburant can be suspended, after laboratory observation, tiny casting with a carburant in graphite particles in the process of melting, It can be suspended in liquid iron even when the current is stopped.
Analysis on the reasons affecting the absorption rate of recarburizer
From the point of view of kinetics and thermodynamics analysis, the oxidation of iron liquid and C - Si - O is related to the equilibrium temperature, namely, O and C in molten iron, Si ferroalloy response will happen, and the equilibrium temperature change according to the target C and Si content is different, the iron liquid above the equilibrium temperature, the priority in the oxidation of carbon, C and O, CO and CO2 generated this liquid iron carbon oxidation loss increase, so the above the equilibrium temperature, carburant absorption rate is reduced, when the carbonization temperature below the equilibrium temperature because the temperature is low, the low saturation solubility of carbon, carbon dissolving diffusion velocity decreased at the same time, and therefore yield is low, When the recarburizer temperature is at the equilibrium temperature, the absorption rate of the recarburizer is the highest.
Mixing dissolution and diffusion of carbon and avoid recarburizer floating in liquid iron surface was burning, in front of the carburant not completely dissolved, stirring time is long, high absorptivity, stirring can also reduce recarburizer holding time, shortening production cycle, to avoid burning of the alloying elements in liquid iron, but mixing time is too long, not only has a great influence on the choice of the stove for life, and in recarburizer dissolves, stirring exacerbate the fluid of the iron carbon loss, therefore, appropriate iron liquid mixing time should be in place to ensure that recarburizer completely dissolved as appropriate.
When the initial carbon content of the iron solution is high, the absorption rate of the recarburizer is slow, the absorption amount is small, the burning loss is relatively high, and the absorption rate of the recarburizer is low. When the initial carbon content of the iron solution is low, the situation is opposite. In addition, silicon and sulfur in the iron solution hinder the absorption of carbon, reducing the absorption rate of the recarburizer. In terms of the influence degree, silicon is the largest, followed by manganese, while carbon and sulfur have little influence. Therefore, in the actual production process, manganese should be added first, then carbon and then silicon.
What should we do when purchasing recarburizer?
In choose recarburizer manufacturers, many customers have said uncertainty, the main reason is because don't know how recarburizer factory product quality, the good is not easy to choose recarburizer manufacturer, price expensive, accept the manufacturer offer, there is a part of the customer to choose recarburizer manufacturer after the price is more appropriate are also not afraid of quality, in short in choose recarburizer manufacturer which on the one hand, has always been a matter of many manufacturers have long!
Choose recarburizer manufacturers don't really need so uncertain, we can check the qualification certificate of product testing, manufacturer operating time a variety of ways, such as honor, fastidious, for the price a little expensive we can consult to the factory to discuss face to face, and for the price lower and lack of recarburizer manufacturers products we can ask recarburizer manufacturer for first samples for laboratory test, qualified after doing a lot of procurement.
Pre-sale and after-sales service is also the most effective way to study the quality of a carbon additive manufacturers, general professional carbon additive manufacturers will regularly on the customer service staff to carry out knowledge training, a professional customer service and pre-sale and after-sales customer satisfaction of the carbon additive manufacturers can be trusted!
Matters needing attention in the process of using recarburizer
Recarburizer (C) is a kind of to increase carbon products, have been used in multiple industry, steel join carburant can effectively improve the hardness and wear resistance of steel, but if too much of the improper use of the carbon steel, at the same time will affect the quality of steel, thus summarizes carburant in which problems should be paid attention to when using or very be necessary, by sorting the use effect of carburant can be effectively promoted.
Note one, the addition time of the recarburizer can not be ignored
If the addition time of recarburizer is too early, it is easy to make it adhere to near the bottom of the furnace, and the recarburizer attached to the furnace wall is not easy to be dissolved into iron, on the contrary, the addition time is too late, it lost the time of increasing carbon, resulting in melting, heating time delay. This not only extends the time of chemical composition analysis and adjustment, but also may cause the harm of ferroalloy caused by excessive heating. Therefore, in the process of adding metal charge, adding carbon agent bit by bit will be better.
If the amount of one addition is too large, it can be combined with the overheating operation of molten iron adopted in the induction furnace to ensure that the absorption time of the recarburizer in molten iron is 10Min. On the one hand, electromagnetic stirring is used to make the carbon extender fully diffused and absorbed, so as to guarantee the absorption effect. On the other hand, it can reduce the amount of nitrogen in the carburizer.
Note two, join method improvement
Don't join in one time, join in batches. Finally melted part, put a part (about a package) of molten iron into the bag, and then back to the furnace to add recarburizer 1-2 times, and then slag, add alloy. There are the following aspects to pay attention to:
1. Recarburizer is difficult to absorb (without calcination)
2. More ash and uneven particle distribution of recarburizer
3. Joining too late
4. The joining method is not correct, so it adopts hierarchical joining. Avoid iron liquid mirror too much slag when added
Try not to use too much rusty material.