Metallurgical characteristics of flux-core welding wire for welding:
(1) deoxidizer and Deoxidizer.
Because nitrogen and oxygen can cause pores or embrittlement of weld bead metal, it is necessary to add Strong deoxidizer such as AL powder and weak deoxidizer (manganese and silicon, etc.) to the flux. As for the self-protecting flux-core welding wire, in the flux, AL should be added as the denitrifying agent. The purpose of adding deoxidizer and deoxidizer above is to purify molten metal.
(2) welding slag composition agent.
Calcium, potassium, sodium and other silicon silicate substances are the composition agent of welding slag (also called slag), which can be used in the flux to maintain the molten pool from air pollution, welding slag can make the welding props have a better appearance and can support the molten pool during full posture welding after rapid cooling. The cover of welding slag can smooth the cooling rate of molten metal, which is especially important for the welding of low alloy steel.
(3) arc stabilizer.
Sodium and potassium can keep arc soft and smooth and reduce splash.
(4) alloy elements.
The increase of manganese, silicon, molybdenum, chromium, carbon, nickel, vanadium and other alloy elements can improve (improve) the strength, ductility, hardness and resistance of molten metal.
(5) gas composition agent.
Fluorite, limestone, etc. need to be added in the self-protection core welding wire to make incineration produce protective gas.