November 10, 2022
The production process of galvanizing line is as follows: cold roll → degreasing → continuous annealing → galvanizing → light finishing → tension setting → roll coating → induction heating → air cooling → quality check → oil coating, weighing and packing. Stamping cracking defects are easy to appear in its production, which will affect the production of users. The causes are as follows:
1. Annealing temperature
Annealing temperature is an important technological parameter in galvanizing process, and it has great influence on yield strength of products. When the annealing temperature is low, the annealing is not enough, the grain is fine, the strength is high, the elongation is low; Annealing temperature is too high, it is easy to lead to abnormally coarse grain, yield strength decreases at the same time tensile strength decreases more severe, the product in the customer stamping forming, tensile process is prone to direct fracture.
2, processing lubrication
The surface roughness of the material will affect the oil storage capacity of the surface. The appropriate surface roughness of the steel coil is also very important for the stamping performance of the material. At the same time, the choice of oil amount is very important, oil amount is too little, the material in the stamping process is not sufficiently lubricated, will lead to material stamping cracking; If the amount of oil is too much, it will slip easily in the process of slicing and forming, which will affect the production rhythm.
3, material thickness and mold clearance
In the process of stamping, the matching between die clearance and material thickness is also an important factor that leads to material cracking.
4. Inclusion and other defects control
The defects such as inclusion and foreign body pressing are very unfavorable to the stamping forming of the stamping product. Because the local elongation of the inclusion part is not enough, it is easy to produce stamping and tensile cracking.
