304 stainless steel tube because of its superior performance, is widely used in all walks of life, sometimes need to carry out deep processing, such as bending, punching, etc., in deep processing will occur fracture. Why does this happen? What causes 304 stainless steel tube to break?
304 stainless steel tube contains a variety of metal elements, such as: chromium, nickel, carbon, iron, etc. It is because of the existence of these metal elements that stainless steel tube has good ductility and corrosion resistance. 304 stainless steel tube material has the advantages of small elongation, large elasticity, high hardening index, short plastic deformation stage from yield to fracture, sometimes after deep drawing deformation will appear deep cracking, from the die will immediately crack, deep drawing deformation sometimes after impact or vibration, Deep drawing deformation can occur after storage or use for a period of time.
The cold working hardening index of austenitic stainless steel is 0.34. 304 stainless steel tube is a kind of metastable, in the process of deformation will occur phase transition and induce martensitic structure, martensitic structure brittle, easy to crack, plastic deformation process, with the increase of deformation, induced martensitic structure content is higher, the greater the residual stress, the more prone to crack in the process of processing.
In addition, the quality of stainless steel tube is determined by the steel strip, in general, 304 stainless steel tube is produced from refining furnace steel strip. Because the market of stainless steel tube brand many, fierce competition, the price between peers is getting lower and lower, profit is getting thinner and thinner, so which side of the low price, which side to receive goods, there will be a medium frequency charge generation.
The so-called intermediate frequency material is a steel strip recovered from stainless steel scrap, but at the beginning of the intermediate frequency batching, the corrosion area is large, making this material difficult to integrate into the market. With the continuous progress of industrial technology, coupled with the fact that the finished product cost of intermediate frequency furnace is much lower than the cost of refining furnace, the raw materials of intermediate frequency furnace are also circulating in the market. Intermediate frequency furnace material impurities, high carbon content, high pipe hardness, easy to break when used for bending processing.
Post time: Jan-31-2023