SELECTIVELY HARDENED DRILL RODS AND SYSTEMS AND METHODS FOR USING AND PRODUCING SAME

摘要

Drill rods having an outer surface that is at least partially non-carburized and at least partially coated with a corrosion-resistant material. The corrosion-resistant material can be chemically bonded to the outer surface of the elongate body. Optionally, the outer surface of the drill rods can define a threaded portion having a plurality of threads and a plurality of roots positioned between adjacent threads. Each thread can have a crest spaced radially outwardly from adjacent roots. Each crest can have a respective hardness, and each root can have a respective hardness. The hardness of the crest of each thread can be greater than the hardness of the roots adjacent to the thread. Systems and methods for making and using the disclosed drill rods are also described.