An airfoil component comprising: an aluminum alloy body comprising at least an airfoil portion and a root portion, the aluminum alloy body substantially forming the shape of the airfoil portion and the root portion, the aluminum alloy body including a peened surface; a metallic layer on at least a portion of the aluminum alloy body; and an electrochemically insulating layer located between and adjoining the aluminum alloy body and the metallic layer for galvanically separating the metallic layer and the aluminum alloy body; wherein: the root portion extends between circumferential sides (164a,164b), a leading side, a trailing side and a radially inner side, and the metallic layer is a continuous coating on at least the circumferential sides (164a,164b) and the radially inner side; the electrochemically insulating layer comprises a polymer that cures at a temperature below 66°C (150°F); and characterized in that: the electrochemically insulating layer comprises a fiber reinforced polymer in which the fibers are polymer fibers or inorganic electrically insulating fibers; and in that the electrochemically insulating layer is directly adjacent to the aluminum alloy body and the metallic layer and adhered to the aluminum alloy body and the metallic layer without the use of an additional adhesive. an aluminum alloy body comprising at least an airfoil portion and a root portion, the aluminum alloy body substantially forming the shape of the airfoil portion and the root portion, the aluminum alloy body including a peened surface; a metallic layer on at least a portion of the aluminum alloy body; and an electrochemically insulating layer located between and adjoining the aluminum alloy body and the metallic layer for galvanically separating the metallic layer and the aluminum alloy body; wherein: the root portion extends between circumferential sides (164a,164b), a leading side, a trailing side and a radially inner side, and the metallic layer is a continuous coating on at least the circumferential sides (164a,164b) and the radially inner side; the electrochemically insulating layer comprises a polymer that cures at a temperature below 66°C (150°F); and characterized in that: the electrochemically insulating layer comprises a fiber reinforced polymer in which the fibers are polymer fibers or inorganic electrically insulating fibers; and in that the electrochemically insulating layer is directly adjacent to the aluminum alloy body and the metallic layer and adhered to the aluminum alloy body and the metallic layer without the use of an additional adhesive. the root portion extends between circumferential sides (164a,164b), a leading side, a trailing side and a radially inner side, and the metallic layer is a continuous coating on at least the circumferential sides (164a,164b) and the radially inner side; the electrochemically insulating layer comprises a polymer that cures at a temperature below 66°C (150°F); and characterized in that: the electrochemically insulating layer comprises a fiber reinforced polymer in which the fibers are polymer fibers or inorganic electrically insulating fibers; and in that the electrochemically insulating layer is directly adjacent to the aluminum alloy body and the metallic layer and adhered to the aluminum alloy body and the metallic layer without the use of an additional adhesive. the electrochemically insulating layer comprises a fiber reinforced polymer in which the fibers are polymer fibers or inorganic electrically insulating fibers; and in that the electrochemically insulating layer is directly adjacent to the aluminum alloy body and the metallic layer and adhered to the aluminum alloy body and the metallic layer without the use of an additional adhesive.