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Difference between bright annealing and general annealing of stainless steel strip

Oct 22, 2020

  General annealing of stainless steel belt means that there is no gas on the surface of stainless steel belt and it is directly put into the furnace for process anneal. This kind of stainless steel strip after annealing treatment also needs to be pickled to remove the iron oxide scale generated on the surface during the delivery process. Due to acid corrosion, the surface roughness decreases, so the gloss is poor, it looks white and not bright.

  Stainless steel strip bright annealing:

  There are two kinds of bright annealing for stainless steel strip. One is annealing under the protection of full hydrogen, which comes from electrolysis or third-party supply with high purity and low dew point, and the other is decomposition with ammonia, after being dried, the decomposed gas enters the furnace as protective gas, which is relatively less pure and dew point. However, the similarity between the two methods is that hydrogen is used as the protective gas. The furnace body has a special structure, and there is a thing called "muffle furnace" inside. The flame heats "muffle furnace" first ", the heat transfer method is used to conduct heat to the strip steel, which avoids the oxidation of the strip steel. Therefore, the strip steel after bright annealing does not need to be pickled again, and the strip steel" basically "maintains the original roughness, therefore, bright annealing strip steel is brighter than ordinary annealing strip steel.