The addition time of recarburizer will affect its effect
Recarburizer, as the name implies, is a kind of product used to increase carbon element, it is used in many industries, such as steelmaking, cast iron when adding a proper amount of recarburizer can be very good to improve the quality of the steel, its hardness and wear resistance and other characteristics will also be improved. But if it is used improperly, the dosage or the timing of adding is not correct, it will have the opposite effect. It will not only not improve the quality of steel or castings, but also affect it to a certain extent. Therefore, when using recarburizer, we need to pay attention to its use method, so that we can improve the effect of its use to a large extent. Specific matters needing attention are as follows.
1）the addition time of recarburizer can not be ignored
If the addition time of recarburizer is too early, it is easy to make it attached to the bottom of the furnace, and the recarburizer attached to the furnace wall is not easy to be permeated by the metal liquid. On the contrary, if the time is too late, the better opportunity for carburization will be lost, resulting in the slow melting and heating time. This not only prolonged the time of chemical composition analysis and adjustment, but also may bring about the damage caused by excessive heating of ferroalloy. Therefore, in the process of adding metal charge, the effect will be better if the recarburizer is layered bit by bit.
If the amount of one addition is too large, it can be combined with the operation of liquid iron overheating used in the induction furnace to ensure that the absorption time of recarburizer in liquid iron is greater than 10min. On the one hand, the electromagnetic stirring effect makes the recarburizer fully diffuse absorption, to ensure the absorption effect, on the other hand, can reduce the amount of nitrogen in the recarburizer.
2） the improvement of the method of joining
Don't do it all at once, do it in batches. Wait until the melting has spread and then add parts. If the process requires, the metal liquid must be added after melting. A recarburizer can be added to a metal package. Then export part of the metal liquid to the bag, and then back to the furnace 1-2 times, and then slag, add alloy. There are several aspects to pay attention to:
1 recarburizer is more difficult to absorb (without calcination);
2 recarburizer ash, particle distribution is not uniform;
3 recarburizer added too late;
4. The method is wrong, and the carburizer is added in layers to avoid the addition of too much slag in the liquid iron mirror;
5. Try not to use too many rusty materials.
Recarburizer plays a very important role in the casting process, and its usage should be determined according to the ratio of other raw materials and the carbon content. In general, different kinds of cast iron is often according to its needs to choose different types of recarburizer. Correct and appropriate use of recarburizer can reduce the production cost of casting.
