Spiral steel pipe cold drawn, hot rolled tube defects, such as cracks or spiral steel high-precision cold drawn pipe after the tank, in the course of the fracture, almost no plastic deformation occurs, it is brittle fracture. Brittle fracture is caused by a variety of reasons. Such as: the precipitate on the grain boundaries, regardless of their intensity stronger or weaker than the matrix strength, all the cause of the cracks. Inclusion on grain boundary segregation is the cause of the problem. In addition, even in far below the yield limit of alternating load, can also lead to fatigue fracture.


Brittle fracture at low stress high strength metallic materials occurs during the organization is far from homogeneous, isotropic material. Organization will have cracks, there will be such as inclusions, porosity defects, these defects can be viewed in the material of microcracks. In addition, the brittle fracture related component temperature use. People through research found that when the temperature drops below a certain temperature, the material will be transformed into brittle conditions, reducing its impact absorption function, a phenomenon known as brittle.