Abstract :
Micromachining abrasive waterjet systems have been developed to cut with jet diameters from 30 to 70 μm. The jets cut, profile, drill, slot and mill metals, glass, ceramics, polymers and composite materials. Profiling trials with 40 μm jets carrying nanometre sized particles of aluminium oxide indicate that cutting should be possible with jet diameters less than 10 μm.
As jet diameters are reduced the ability to quickly stop and start cutting jets becomes increasingly important, particularly when drilling holes. Diamond seated valves are described that have the potential to be developed to carry out tens of jet on/off cycles per second.