Influence of Ni–P coating on fatigue life of an Al2O3f/Al composite wire

An Al2O3f/Al composite wire was Ni–P coated by means of an electroless plating route. Fatigue life and residual properties of the coated and uncoated composite wires were investigated. It was found that the fatigue life, residual strength and residual modulus of the composite wire could be improved by the Ni–P coating, indicating that Ni–P coating could increase the fatigue resistance of the composite wire. Finite-element analysis (FEA) was performed to understand the mechanism of the prolonged fatigue life. FEA indicated that Ni–P coating could both restore the load-bearing capability of broken surface fibers and reduce the stress and strain concentrations caused by broken fibers, hence resulting in a higher fatigue resistance of the Ni–P coated composite wire than that of the uncoated one.