Dry Sliding Wear Behavior of Boron-Doped AISI 1020 Steels

In the present study, the wear properties of AISI 1020 steels produced by a casting process with different boron contents were investigated, using a pin-on-disc tribometer under dry sliding conditions.The friction coefficients of undoped AISI 1020 steel, 0.002 and 0.01 wt% boron-doped samples were 0.33, 0.27, and 0.32, respectively.The addition of boron into AISI 1020 steel led to a decrease in the friction coefficient, due to the lubricating effect of boron; X-ray diffraction showed that both Fe2B and FeB phases are present in the boron-doped samples, both of which cause this lubrication.The wear test results also showed that the wear rate of the 0.002 wt% boron-doped AISI 1020 sample decreased compared to the undoped AISI steel, and then increased in the 0.01 wt% boron sample.Therefore, the wear resistance of AISI 1020 steel is increased with the addition of small amounts of boron.Scanning electron microscopy results indicated that the characteristic wear mechanism for the boron-doped sample surfaces was plastic deformation and mild abrasive wear; for undoped AISI 1020 steel, cracking and spalling were observed instead.