Defects of low temperature steel tube when drawing
1. The cause of cracking formation
Low-temperature austenitic steel pipe cold work hardening index (low-temperature steel pipe 0.34). Cryogenic steel is metastable, deformation occurs in the phase transition, induced martensite phase. Martensitic phase is brittle, so prone to cracking. In the plastic deformation, with the increase of the deformation, the higher the martensite phase content, the greater the residual stress, and the easier the cracking process.
2. Surface scratches the formation of reasons
Cracks on the surface of the drawn parts of the low-temperature steel pipe are mainly due to the relative movement of the workpiece and the mold surface, resulting in direct friction between the billet and the mold surface under certain pressure, and the deformation heat of the billet makes the billets and metal scraps deposited Mold surface, the workpiece surface scratches scratches.
