A water jet machine, also known as a water jet cutter, is a type of cutting machine that uses a high-pressure stream of water to cut a variety of materials, including metal, plastic, glass, ceramics, and composites. The stream of water is mixed with an abrasive material, such as garnet, that allows the water to cut through even very hard materials.

Water jet machines typically consist of several components, including a high-pressure pump, an intensifier that increases the pressure of the water, a cutting head that directs the stream of water and abrasive at the workpiece, and a CNC (computer numerical control) system that controls the movement of the cutting head.

The waterjet cutting process is a cold cutting process, which means that the material is cut without being heated, which eliminates the potential for thermal distortion, material warping, or other thermal-related issues. This makes the waterjet cutting suitable for cutting materials that are heat-sensitive or have a low melting point, like aluminum, copper, and titanium.

The process can be used to cut a wide range of materials, from delicate materials like foam and rubber, to tough materials such as stainless steel, aluminum, and titanium. Water jet cutting can also cut very thick material with ease and create very intricate shapes and geometries in the material.

Water jet machines are used in many different industries, including aerospace, automotive, construction, and manufacturing, for cutting and shaping various materials with high precision and accuracy. They require skilled operators, proper maintenance and calibration for optimal performance and accurate cuts.