Erosion resistant fluid passageways and flow tubes for earth-boring tools, methods of forming the same and earth-boring tools including the same

An earth-boring tool, comprising:

• a tool body having at least one cutting structure mounted thereto;
• a fluid passageway extending through at least a portion of the tool body;
• and
• a hardfacing material covering a surface of the tool body in a region of the body susceptible to erosion from fluid when the fluid is caused to flow through the fluid passageway.

An earth-boring tool comprising:

• a body having at least one cutting structure secured thereto;
• a fluid passageway extending through at least a portion of the body;
• and
• a mass of hardfacing material covering at least a portion of an outer surface of the body, at least a portion of the mass of hardfacing material being exposed within the fluid passageway.

A method of forming an earth-boring tool, the method comprising:

• forming a body having a fluid passageway extending therethrough;
• securing at least one cutting structure to the body;
• and
• covering at least a portion of a surface of the body with a hardfacing material, the at least a portion of the surface of the body being located in a region of the body susceptible to erosion from fluid when the fluid is caused to flow through the fluid passageway.