Mechanical properties and tribological behavior of Fe/nano-diamond composite prepared by hot-press sintering

In the present study, Fe matrix composites reinforced with nano-diamond (ND) particulates were fabricated by hot-press sintering. The influence of the concentration of ND on the mechanical and tribological properties of as-sintered Fe/ND composites was investigated. The microstructures and properties of the Fe/ND composites were examined using X-ray diffraction, Raman spectroscopy, and scanning electron microscopy. A pearlite microstructure is formed due to the reaction between Fe and ND in the sintering. The presence of ND provides higher hardness, compressive strength, and flexural strength. The composite with 1 wt% ND exhibits 51.5% higher hardness, 37.4% higher compressive strength, and 76.2% higher flexural strength than sintered Fe. In addition, the wear resistance will increase as the ND concentration increases. Fe/2 wt% ND composite exhibits much lower friction coefficient (COF) and higher wear resistance than a Fe/1 wt% ND composite and sintered Fe. •A microstructure of pearlite was formed in the sintered Fe/ND composites.•Fe/ND composites exhibit higher hardness, compressive strength, and flexural strength than sintered Fe.•Fe/ND composite with higher content of ND produce lower friction coefficient (COF) and higher wear resistance.