A plasma spraying apparatus includes a main torch and an auxiliary torch. The main torch includes a first electrode including a spraying material discharge hole, a first mantle, and a first insulator including a first plasma gas introducing port. The auxiliary torch includes a second electrode, a second mantle, and a second insulator including a second plasma gas introducing port. A spraying material supplied from the spraying material discharge hole is melted at the axial center of plasma that is formed on the central axis of the first electrode by the first electrode and the second electrode, and a gas introducing part that introduces gas is provided on an inlet side of an opening part and/or in a tapered part provided between the opening part and the first insulator in the first mantle.

A method of forming additive energy directors according to various exemplary embodiments can include dispensing a molten material onto a substrate at a predetermined location. The method also includes solidifying the molten material to form at least one additive energy director onto the substrate.

A composite wire for use with a wire arc spray system and related methods. The composite wire can include: a low melting point material at a core region thereof and a cladding including a metal surrounding the core region, the low metal point material having a melting point less than that of the metal, wherein the low melting point material includes a polymer in the form of a powder having particles having a size of from approximately 1 nanometer to approximately 100 nanometers.