Tribological Property of Cu14Al4.5FeNi Bronze and Its Plasma Sprayed Coating

The expense and difficulty of machining novel aluminum bronze blocks in some zones of dies and the difficulty of installing due to the brittleness of the blocks can be solved by using the aluminum bronze coating. Cu14Al4.5FeNi coating was prepared on a 45# carbon steel substrate by plasma spraying. Friction and wear of the coating and Cu14Al4.5FeNi alloy under boundary lubrication regime in a 20# engine oil were comparativelly investigated in a reciprocating sliding mode. Scanning electron microscopy, energy dispersion spectroscopy and X-ray diffraction were employed to analyze the morphologies and phase structures of the coating and alloy. The intragrain phases, γ2 and the k phases, refined and hardened the microstructure of the alloy and coating. The brittle eutectoid (α+γ2) phase was eliminated in the coating due to high solidification rate in plasma spraying. In boundary lubrication regime, the main wear mechanisms of the alloy and coating were abrasive and adhesive wear. The friction and wear of coating were better than that of Cu14Al4.5FeNi alloy at low load. The friction coefficient and wear loss of the coating increased dramatically as the load was higher than 6.40 MPa. The steel substrate with plasma sprayed Cu14Al4.5FeNi coating can be a good subsitution of Cu14Al4.5FeNi alloy under low load conditions.