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Decarburization and overburning during heating of stainless steel processing

Date:2021-02-01 Font size

Stainless steel processing decarburizes when heated


  ① The main factor that reduces the carbon concentration is the reaction between the surface carbon and the hydrogen, oxygen, and carbon dioxide in the air.


  ②The surface of decarburized steel after quenching is prone to reduce fatigue strength, wear resistance and surface hardness, and participates in tensile stress to form surface network cracks.


  ③Oxidation refers to the phenomenon in which iron and alloy on the surface react with hydrogen, oxygen, carbon dioxide, etc. in the air to form an oxide film when steel is heated.


  ⑥ After the high temperature workpiece is oxidized, its dimensional accuracy and surface brightness will be reduced, and it also has an oxide film and poor hardenability, which is prone to quenching points.


  Overheating phenomenon in stainless steel processing: The mechanical properties of the parts are reduced, which is caused by overheating during the heat treatment process, which is very easy to cause the austenite grains to become coarse.


   Overburning phenomenon of stainless steel processing:


  ① In the work, it is necessary to avoid the occurrence of overburning, because once it occurs, the organization can only be scrapped and cannot be restored.


  ②Excessive heating temperature causes coarse austenitic stainless steel plate grains, and local melting or oxidation of the grain boundaries leads to weakening of the grain boundaries. Over-firing will cause deterioration of the performance of the steel, and cracks will be formed during quenching.


   Chemical polishing for stainless steel processing. Its advantages are low investment in processing equipment, ability to throw complex parts, fast speed, high efficiency, and good corrosion resistance. It is suitable for processing small batches of complex parts and products with low brightness requirements for small parts.


  Electrochemical polishing. This is a polishing process that maintains gloss for a relatively long time. Its process is stable, less pollution, low cost, and good corrosion resistance. It is suitable for mass production, mainly used in products, export products, products with tolerance, and its processing technology is stable and easy to operate.


   Its advantage is that the processed parts have good leveling and high brightness. However, the labor intensity is high, the pollution is serious, and the complex parts cannot be processed, and the gloss is not consistent, the gloss retention time is not long, and it becomes stuffy and rusty. More suitable for processing simple parts, medium and small products.