Core wire is mainly made from strip and alloy powder by mechanical pressing. The amount of cored wire decreases with increasing calcium yield and is related to the type of cored wire and varies considerably. Under the condition of the same calcium recovery rate, the mass fraction of calcium in the seam pure calcium cored wire is higher and the advantage of the amount is obvious.
Calcium treatment of steel and selection of cored wire. The traditional core wires used for calcium treatment mainly include:
1. calcium-silicon wire: the powder in the wire is Si-Ca alloy. The advantage is that the rate of calcium absorption is stable and calcium is not easily oxidized by air. The disadvantage is that the increase of silicon is serious, and it is not applicable to low-silicon steel.
2. Calcium-iron wire: the powder inside the core wire is pure calcium metal particles, which are mixed with iron powder according to a certain proportion, but there is a lot of smoke in the feeding process, which is easy to cause steel splashing, the calcium recovery rate is not stable, and the calcium metal is easy to be oxidized by moisture, thus shortening the shelf life of the wire.
3. Calcium Aluminum Wire: The powder inside the core wire can be made from CaAl alloy by crushing, or by mixing pure calcium particles with aluminum powder mechanically. This line is characterized by a stable and high calcium recovery rate, and there is no obvious silicon increase in the steel after wire feeding.
