Manufacture of drill bits using sintering

How PDC drill bits are made?

A PDC (polycrystalline diamond compact) drill bit has cutting elements on its leading end that include sintered polycrystalline diamond tables bonded to a substrate.

The sintered table includes diamond grains, metal-solvent catalyst and interstitial regions.

The amount of metal-solvent catalyst is about 1-6wt%.

The diamond grains and the metal-solvent catalyst collectively exhibit a specific magnetic saturation of about 15 Gauss.cm3/gram or less.

Refer to this patent for more information.

How polycrystalline diamonds are made by sintering?

Polycrystalline diamond compact include a substrate and a sintered diamond table bonded to the substrate.

The diamond table includes diamond grains having diamond-to-diamond bonding.

The diamond table is formed by mechanically milling non-diamond carbon and a sintering aid material to form a carbon-saturated sintering aid powder.

 The diamond particles are sintered in the presence of carbon-saturated sintering aid to form a polycrystalline diamond table.

The carbon-saturated sintering aid particles catalyze the formation of diamond-to-diamond bonding between the diamond particles to form the polycrystalline diamond table.

Refer to this patent for more information.

How to make a boron carbide based drill bit using sintering?

A rotary drill bit can be  made by sintering boron carbide particles in a aluminium matrix.

To make the drill bit, first, boron carbide particles are compacted and sintered together to form a body having the shape of the drill bit’s chamber.

Then, molten aluminum is infused to form a solid matrix which surrounds the boron carbide particles.

The infiltrating aluminum Cools the resulting composite, giving it a rigid, powerful structure with extremely high thermostability.

Refer to this patent for more information.

More articles on sintering