Wear Behavior of Layers Produced by Boriding and PVD + Boriding Treatments ON AISI H13 Tool Steel

摘要

In this work, boride layers of high hardness and wear resistance were produced on AISI H13 tool steel through thermo-reactive treatment in borax bath with addition of 10% aluminum. Additionally, Physical Vapor Deposition (PVD) coating was performed over the boride layers for some samples. The samples were then characterized by optical microscopy (OM), scanning electron microscopy (SEM), Vickers hardness testing and free ball microabrasive wear tests. The boronizing was carried out at 900 °C with a bath residence time of 4 hours, followed by oil or air cooling. The boronizing treatment produced layers with a mix of FeB and Fe_2B borides and an average thickness of 70 μm. The layer hardness was in the range of 1500 to 1700 HV. The PVD treatment produced an AlTiCrN layer with a depth of 5 μm and with a hardness higher than 3000 HV. Samples with boriding-PVD duplex treatment showed the best wear performance, followed by the borided sample and the uncoated quenched and tempered AISI H13 steel.