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      High precision cold drawn tubeLow-temperature embrittlement refers to the phenomenon that steel pipes transform from ductile to brittle at low temperatures and then fail. The reasons for this problem may be as follows:
       1. When the dislocations generated by the dislocation source during deformation are blocked by obstacles (such as grain boundaries, second phases, etc.), the local stress exceeds the theoretical strength of the cold-rolled precision bright steel pipe and microcracks occur.
       2. Several accumulated dislocations synthesize a microcrack at the grain boundary.
       3. Reaction at the intersection of slip zones causes immobile dislocations.