Enhanced surface properties of iron by in situ hard nickel coating

Abstract

Abstract In the current study, hard facing nickel alloy powders were coated in situ on pure iron by uniaxial hot pressing under vacuum atmosphere to improve its hardness and wear properties. The nickel alloy powders were placed onto the iron powders within a graphite die and then sintered at 1000 °C under 40 MPa for 10 minutes. Hardness and wear properties were studied by using a Vickers hardness tester and a ball-on-disk tribometer, respectively. The wear rates of the samples were evaluated using a sliding velocity of 0.13 m × s−1 under normal loads of 20, 30, 40 and 50 N at room temperature. The interface layer between the nickel layer and pure iron substrate was also evaluated by scanning electron microscopy and energy dispersive spectroscopy. The results showed that sintered samples exhibited strong bonding at the interface. The hardness and wear properties of the materials increased effectively after nickel coating.