Patent attributes
A method of making a cutter structure (1) comprises placing a pre-formed body (4) of hard material having a surface topography in a canister, placing an aggregated mass of grains of superhard material (2) over said surface topography, placing a punch (10) in contact with the superhard material (2), the punch (10) having a surface with a surface topography inverse to that of the hard material body to imprint a pattern in the superhard material (2) complementary to the surface topography of the punch (10). The surface of the punch (10) contacting the superhard material (2) being formed of a ceramic material that does not react chemically with the superhard material (12) and/or a sinter catalyst for the superhard material (2). A pressure of greater than 3 GPa is then together with a temperature sufficiently high for the catalyst to melt to form the cutter structure (1) with a layer of polycrystalline superhard material bonded to the hard material and having a surface topography corresponding to the surface topography of the hard material.
