Combined field assisted sintering techniques and HTHP sintering techniques for forming polycrystalline diamond compacts and earth-boring tools

A method of using a sintering system, comprising:

• disposing, within a container of a pressure cell, a particle mixture to be sintered;
• subjecting the particle mixture to a high temperature high pressure (HTHP) sintering process to form a polycrystalline diamond material, subjecting the particle mixture to the HTHP sintering process comprising passing an electrical current through a first electrically conductive pathway to heat the particle mixture;
• and
• pulsing another electrical current through a second electrically conductive pathway during at least a portion of the HTHP sintering process, the second electrically conductive pathway passing through the particle mixture and being electrically isolated from the first electrically conductive pathway.

A method of using a sintering system, comprising:

• disposing, within a container of a pressure cell, a particle mixture to be sintered;
• passing an electrical current through a first electrically conductive pathway and heating the particle mixture to a temperature of at least about 1,300° C.;
• applying a pressure to the particle mixture within the container of the pressure cell to at least about 5.0 GPa;
• and
• pulsing another electrical current through a second electrically conductive pathway, the second electrically conductive pathway passing through the particle mixture and being electrically isolated from the first electrically conductive pathway.