Dry sliding wear behavior of borided hot-work tool steel at elevated temperatures

In the present study, the surface of AISI H13 hot-work tool steel was borided with EKabor II powders using powder pack-boriding method. The process was carried out at 800, 900 and 1000 °C temperatures for 2, 4 and 6 h periods. The wear tests were carried out using a ball-on disc tribometer at room temperature and 500 °C on borided and untreated AISI H13 hot-work tool steel. Scanning electron microscope (SEM), optical microscope, 3D profilometer, X-ray diffraction analysis and micro-hardness tester were used in the evaluation of micro-structure and wear data. The increase in the boriding temperature and boriding period led to increased thickness and hardness of the boride layer. Boriding at 800 °C resulted with formation of Fe2B, Mn2B, Cr5B3, phases, while FeB, Fe2B, Mn2B, and Cr5B3 boride phases occurred at 900 and 1000 °C. Dominant wear mechanisms were microcrack-induced plastic deformation during high temperature wear tests; oxidation and microcrack formation during room temperature wear tests; and oxidation and severe plastic deformation for the untreated specimen.