Burst at the bulging - 1.7709 steel

Burst at the bulging - 1.7709 steel - Cold drawing defects

Figure 1: Treatment: Spheroidised. Magnification: 6.5x. Sampling/Specification: Bulge area - sample 1. Testing result: Through a surface defect the bulge part is burst.

Figure 2: Treatment: Spheroidised. Magnification: 16x. Sampling/Specification: Wire surface - sample 2. Testing result: Surface defect in longitudinal direction.

Defect name: Burst at the bulging
Record No.: 429
Type of defect (Internal/Surface): Surface
Defect classification: Cold drawing defects
Steel name: 1.7709 steel
Steel composition in weight %: No data.
Note: It can come to bursts at the wire surface of cold upsetting steels by the compressing to screws or tools. The strength of the bursts is dependent from the degree of the cold forming, the size of the existing defects and possible anomalies of the structure. A pincher and pre-material defects, with an slag in surface proximity, were the reason for the processing problems in this case.
Rod wire 12.00 mm round - pickled, annealed.
Reference: Not shown in this demonstration version.