Nitrogen implantation in Interstitial-Free steel was evaluated for its impact on metal transfer and 1100 Al rider wear. It was\r\ndetermined that nitrogen implantation reduced metal transfer in a trend that increased with dose; the Archard wear coefficient\r\nreductions of two orders of magnitude were achieved using a dose of 2e17 ions/cm2, 100 kV. Cold-rolling the steel and making\r\nvolumetric wear measurements of the Al-rider determined that the hardness of the harder material had little impact on volumetric\r\nwear or friction. Nitrogen implantation had chemically affected the tribological process studied in two ways: directly reducing the\r\nrider wear and reducing the fraction of rider wear that ended up sticking to the ISF steel surface. The structure of the nitrogen\r\nin the ISF steel did not affect the tribological behavior because no differences in friction/wear measurements were detected after\r\npostimplantation heat treating to decompose the as-implanted ??-Fe3N to ??-Fe4N. The fraction of rider-wear sticking to the steel\r\ndepended primarily on the near-surface nitrogen content. Covariance analysis of the debris oxygen and nitrogen contents indicated\r\nthat nitrogen implantation enhanced the tribo-oxidation process with reference to the unimplanted material. As a result, the\r\nreduction inmetal transfer was likely related to the observed tribo-oxidation in addition to the introduction of nitridewear elements\r\ninto the debris. The primary Al rider wear mechanism was stick-slip, and implantation reduced the friction and friction noise\r\nassociated with that wear mechanism. Calculations based on the Tabor junction growth formula indicate that the mitigation of the\r\nstick-slip mechanism resulted from a reduced adhesive strength at the interface during the sticking phase.
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