Effects of microstructural parameters on the delamination of steel filaments with various true strain and carbon content have been experimentally investigated. The filaments were fabricated by cold drawing process with the true strain range from 4.12 to 4.32 and the carbon contents of 0.82 and 1.02 wt.%. Torsional ductility of the filaments was measured by using torsion-torque tester. Microstructural parameters, such as lamellar spacing, the thickness and morphology of cementite, were identified by using both transmission electron microscopy (TEM) and voltage-pulsed atom probe tomography. Delamination phenomenon was observed in the filaments with 1.02 wt.% C regardless of true strain, while it was not observed in the filaments with 0.82 wt.% C. As the true strain and carbon content increased, the lamellar spacing (P) and cementite thickness (tc) decreased. Spherical-shaped cementites and clusters of thicker cemetite were also found in the filament with 1.02 wt.% C. In order to elucidate the occurrence of delamination, its microstructural dependence was discussed in terms of microstructural parameters mentioned above.
Cementite dissolution and delamination of hyper-eutectoid pearlitic steel filaments for tire cords
2007
7 Seiten, 12 Quellen
Aufsatz (Konferenz)
Englisch