Method and apparatus for selectively leaching portions of PDC cutters already mounted in drill bits

摘要

A polycrystalline diamond compact (PDC) drill bit having a plurality of PDC cutters, each having a body of diamond crystals containing catalyzing material, is coated with a material which is impervious to a given acid. After the coating is dried, a segment of the coating is removed and acid is supplied to the body of diamond crystals to leach out the catalyzing material contained within the exposed portion of the body.