HIGH-TEMPERATURE WEAR MECHANISM OF CAST HOT-FORGING DIE STEEL 4Cr3Mo2NiV

The wear behaviors of cast hot-forging die steel 4Cr3Mo2NiV were examined at a temperature range from RT to 600℃. The wear mechanism was clarified through analyzing the morphologies, compositions and structures of wear surface and wear debris, which were obtained by using SEM, XRD and EPMA. The results showed that the predominant mechanism of high temperature wear is oxidation wear and fatigue delamination, which alternately occur to make the coefficient of friction extensively undulate during wear processes. The oxides of wear surface are Fe_2O_3 and Fe_3O_4. The wear rate is reduced by oxidation wear, increased by fatigue delamination and the wear debrises are brittle lumps.