| 摘要 |
<p>A method of removing a diamond catalyst/solvent and/or one or more metal carbides from a polycrystalline diamond (PCD) body by exposing at least a portion of the PCD body to a leaching solution. The leaching solution comprises nitric acid and at least one other mineral acid diluted in water. The nitric acid can comprise 2-5 % by weight of the nitric acid and water mixture and/or the leaching solution can comprise 0.2-1.2 molar nitric acid. The other mineral acid can comprise one or more of hydrochloric acid, sulphuric acid, phosphoric acid and hydrofluoric acid, at a concentration of up to 7 molar. Leaching can be done at or above the boiling point of the leaching solution and can be used to remove cobalt, nickel and/or iron or a carbide of tungsten, titanium, niobium, tantalum, zirconium, molybdenum, chromium and/or vanadium.</p> |
