During the smelting, forging and rolling process of Hot sales 201 or 430 stainless steel coil, the following problems often occur:
Shrinkage cavity: The shrinkage cavity formed when the molten steel shrinks in the steel mold is called a shrinkage cavity.
Transverse crack: refers to the transverse crack that occurs on the surface of the steel ingot, generally on the steel ingot, the depth is generally shallow, and can be removed by fine grinding.
Longitudinal crack: refers to the longitudinal crack on the surface of the steel ingot, generally in the upper part and corner of the steel ingot, and the crack in the upper part is very deep and difficult to eliminate by grinding.
Scarring: On the surface of the steel ingot, the shell-like or tumor-like metal splashed and stuck is called scarring, and the scarring mostly occurs at the lower part of the steel ingot.
Heavy skin: When the edge of the low magnification test piece shows an irregular dark color and looseness, a large number of oxide inclusions (mainly ferrous oxide) are gathered around it, which is called overturning.
Surface inclusions: refers to the non-subtractive inclusions visible to the naked eye embedded in the surface of the steel ingot.
Surface pores: refers to the tiny pores exposed to the naked eye on the surface of the steel ingot, which are more common in the middle and lower parts of the steel ingot, generally not deep, and can be removed by finishing.
Explosion: The cracking occurs when the surface of the steel ingot is extremely cold, because the cracking often makes a noise, so it is called bursting.
Rising: The head of the steel ingot is irregularly raised, this defect is called rising, also called rising.
Reticulate: The reticulated protrusions on the surface of the steel ingot are called reticulates.
Hemp pits: The pits on the surface of the ingot are called pits.
Double pouring: visible reconnection marks around the surface of the ingot
Flash: The metal flakes that exist at the head or tail of the ingot perpendicular to the surface of the ingot are called flash.
Flying fins: The thin sheets formed on the surface of the steel ingot perpendicular to the surface of the steel ingot are called flying fins.
Bubble: Bubble is the defect of the steel ingot or just due to the poor degassing and deoxidation of molten steel or the wet raw material of the steel injection system. Generally, it is divided into subcutaneous bubbles and internal bubbles. (Prevention method: The oxidation, boiling, reduction and deoxidation of molten steel should be good, the furnace and all refractory materials in contact with the molten steel should be dry, the tapping groove, steamed buns, hand plates, molds, etc. should be dry, the rust spots of the mold should be cleaned, and the oil should be thin and even. )
White spot: The white spot is actually a kind of fine crack. It is a radioactive and irregular sawtooth crack on the horizontal low-magnification sample just now. On the vertical low-magnification sample, it is a silver bright spot of a round or elliptical star, so it is called a white spot. .