Phase Structure and Lubricity of In-Situ Generated Protective Layer on Worn Metal Surfaces in Presence of Mg₆Si₄O₁₀(OH)₈

A mechanochemical reconditioner package has been investigated in our laboratory which could be used to generate an in situ protective layer on worn metal surfaces as a result of mechanochemical reactions between worn tribosurfaces, wear debris and a special reconditioner formulation. The main constituent in the reconditioner formulation chemistry is magnesium silicate hydroxide, Mg₆(Si₄O₁₀)(OH)₈. HRTEM analyses have displayed that the protective layer consists mainly of cementite nanocrystals with crystalline anisotropy. Nanoparticles of magnet iron oxide (Fe₃O₄) and iron peroxide (FeOOH) are dispersed on the habit planes of nanocrystalline cementite matrix. The protective layer obtained exhibits very smooth top surface and excellent tribological characteristics.