Polycrystalline abrasive compacts

A method of manufacturing a polycrystalline ultrahard abrasive material including the steps of

• providing a plurality of ultrahard abrasive particles selected from the group consisting of diamond and cubic boron nitride,
• manipulating the surface chemistry of the ultrahard abrasive particles to render the surfaces of the particles to be vitreophilic, the vitreophilic surfaces to form chemical bonds with oxides, the vitreophilic surfaces comprising any of oxides and hydroxides of the material of the ultrahard abrasive particles,
• colloidal suspension coating the manipulated surfaces of the ultrahard abrasive particles in a suspension with a matrix precursor material via the hydrolysis and polycondensation of alkoxides in the presence of deionised water, thereby to grow coats of hydrated oxide precursor materials onto the surfaces of the vitreophilic suspended particles, the deionised water being added to the suspension over a period of at least one hour,
• treating the coated ultrahard abrasive particles to render them suitable for sintering, and
• consolidating and sintering the coated ultrahard abrasive particles at a pressure and temperature at which they are crystallographically or thermodynamically stable.