Comparative research on dry sliding wear of hot-dip aluminized and uncoated AISI H13 steel

In order to improve the elevated-temperature wear resistance of steels, an aluminized coating consisting of FeAl and Fe3Al was prepared on AISI H13 steel by hot-dip aluminizing and subsequently high-temperature diffusion. Dry sliding wear tests were conducted for the aluminized and uncoated AISI H13 steel against AISI M2 steel at room temperature and 600 °C, respectively. Compared with the uncoated H13 steel, the aluminized steel possessed excellent elevated-temperature wear resistance, in spite of worse room-temperature wear performance. As the load increased, the wear rate of the aluminized steel rapidly increased at room temperature, but maintained extraordinarily low values at 600 °C. On the contrary, with an increase of load, the wear rate of H13 steel marginally increased at room temperature, but rapidly increased at 600 °C. The aluminized steel seemed to be suitable to the applications involving elevated-temperature sliding. Interestingly, the excellent elevated-temperature wear performance of the aluminized steel was noticed to be attributed to the protection of the thin tribo-oxide layer with a strong support from high thermal-strength intermetallic compound.