Mechanical and metallurgical characterisation of electroformed nickel for helicopter erosion shield applications

Based on erosion shield cut ups, electroformed nickel appears to be essentially isotropic in nature due in part to the extremely fine crystalline microstructure. As mechanical property variability is greater with electroformed nickel when compared to wrought products it is essential that integral mechanical property test pieces are employed in order to be able to fully characterise the properties within the electroform. Certain electroforming defects have been shown to lower high cycle fatigue life; hence it is vitally important that in case of critical components, robust Non-Destructive Inspection (NDI) techniques are employed to ensure they are eliminated from production components.