Multi-layer hardfacing film for earth-boring tool erosion resistance

The patent applies hardfacing material to the tool surface before the tool is put into service. This preliminary protective action prevents erosion damage from occurring in the first place, rather than repairing damage after it occurs. The hardfacing layer is deposited on the external surfaces of the tool body, particularly on surfaces exposed to drilling fluid flow, to create a wear-resistant barrier that extends the tool's service life.

The patent uses composite hardfacing materials that combine a metal matrix with dispersed hard particles (such as carbides, oxides, or ceramics). This composite structure provides both the toughness of the metal matrix and the wear resistance of the hard particles. The composite material approach allows the tool to achieve superior erosion resistance while maintaining structural integrity, resolving the contradiction between improved reliability and increased complexity.

The hardfacing material is applied to the tool surface during the manufacturing process, before the tool is put into service. This preliminary hardening action ensures that the wear-resistant layer is already in place when the tool begins operation, eliminating the need for subsequent hardening operations or repairs during the tool's service life.

The patent employs various deposition techniques (such as thermal spray, plasma spray, or cold spray) that allow the hardfacing material to be applied in a controlled manner with specific thickness and composition parameters. By optimizing these parameters, the manufacturing process achieves the desired wear resistance while minimizing process complexity and cost.