Sticked flaky things, which are in places on the surface,
are described as scab. They usually only have connection to the basic material
in a place. Scabs can appear as a pre-material defect of the billet or block or
they can arise from local pincher at the hot forming. In most cases a metallographic
specimen examination can give information about the origin of the scabs. In this
case it is defects of the pre-material. At the microsections non metallic oxide
slags and an anomaly of the sulfides were stated in the environment of the scabs.
On the other hand, the scab consists of another material.
Rod wire
16,50 mm round - solution annealed , pickled
drawn and sharpened at 15,00 mm round