Non-destructive leaching depth measurement using capacitance spectroscopy

A method of characterizing a quality of a polycrystalline structure, the method comprising:

• obtaining a leached component comprising the polycrystalline structure, the polycrystalline structure comprising a leached layer and an unleached layer, the unleached layer positioned adjacent to the leached layer, the leached layer having at least a portion of a catalyst material removed from therein;
• measuring capacitance values of the leached component at multiple frequencies of an electrical signal, the electrical signal provided to the leached component by a capacitance measuring device,
• wherein each capacitance value of the capacitance values is measured at a respective frequency of the multiple frequencies of the electrical signal;
• selecting a lowest capacitance value from among the measured capacitance values;
• and
• identifying an actual leaching depth value that corresponds to the selected lowest capacitance value using capacitance to leaching depth mapping information,
• wherein a depth of the leached layer of the leached component is estimated to equal the leaching depth value.

A system for measuring capacitance of a polycrystalline diamond compact cutter, the system comprising:

• a capacitance measuring device comprising a first terminal and a second terminal;
• the polycrystalline diamond compact cutter having a leached layer and an unleached layer adjacent to the leached layer, the leached layer having at least a portion of a catalyst material removed from therein;
• a first wire for electrically coupling the first terminal to a first surface of the polycrystalline diamond compact cutter;
• and
• a second wire for electrically coupling the second terminal to a second surface of the polycrystalline diamond compact cutter, the first surface and the second surface being on opposite sides of the leached layer and the first surface being a surface of the leached layer;
• a press for firmly engaging the wires with the respective surfaces to form a circuit,
• wherein the capacitance measuring device is operable to:
• provide an electrical signal to the polycrystalline diamond compact cutter to measure capacitance values of the polycrystalline diamond compact cutter,
• measure the capacitance values of the polycrystalline diamond compact cutter at multiple frequencies of the electrical signal,
• select a lowest capacitance value from anion, the measured capacitance values, and
• determine a leaching depth value that corresponds to the selected lowest capacitance value using capacitance to leaching depth mapping information.