Waterjet cutting is a subtractive manufacturing process that uses a highly compressed jet of water at very high speed (more than three times the speed of sound in air).
The water jet removes the cut material from the cutting gap by erosion and shearing. If abrasive powder is also used, the cohesion of the workpiece material is also broken by micromachining. During the process, the water jet passes through the water nozzle and draws the abrasive into the mixing chamber. The water and abrasive then enter the hydroabrasive nozzle and are formed. The water jet is used to accelerate the abrasive grains, which reach speeds in excess of 300 m/s.