Functionally graded WC-Co/NiAl HVOF coatings for damage tolerance, wear and corrosion protection

► NiAl/WC-Co functionally graded coatings (FGC) manufactured by HVOF spraying. ► Lower stress discontinuity than pure WC-Co at the coating/substrate interface. ► Damage tolerance conferred by compressive stresses in underlying coating layers. ► Better cyclic impact resistance than pure WC-Co layers (reduced cracking). ► The FGC coating is dense and free from significant interconnected porosity.