EARTH-BORING TOOLS HAVING PARTICLE-MATRIX COMPOSITE BODIES, METHODS FOR WELDING PARTICLE-MATRIX COMPOSITE BODIES AND METHODS FOR REPAIRING PARTICLE-MATRIX COMPOSITE BODIES

摘要

Methods for welding a particle-matrix composite body (120) to another body (154) and repairing particle-matrix composite bodies (120) are disclosed. Additionally, earth-boring tools (110) having a joint that includes an overlapping root portion and a weld groove having a face portion with a first bevel portion and a second bevel portion are disclosed. In some embodiments, a particle-matrix bit body (120) of an earth-boring tool (100) may be repaired by removing a damaged portion, heating the particle-matrix composite bit body (120), and forming a built-up metallic structure thereon. In other embodiments, a particle-matrix composite body (120) may be welded to a metallic body (154) by forming a joint, heating the particle-matrix composite body (120), melting a metallic filler material forming a weld bead and cooling the welded particle-matrix composite body (120), metallic filler material and metallic body (154) at a controlled rate.