Erosion of an Air-injected Plain Waterjet (iPWJ)

The article describes the fundamental characteristics of a plain waterjet (PWJ) tool enhanced by air. An injection-type abrasive waterjet (AWJ) head was used, in which the entrained abrasive was replaced by a defined air input. A two-phase PWJ was created by the injection principle (iPWJ). In dependence on the air pressure supplied, the footprint of the perceived jet tool was characterized. A standard aluminum alloy EN AW-5083 was chosen for the material to be machined. The experiments were designed with two water pressure levels, and four pressure conditions of the air inlet that varied from blocked air, atmospheric conditions, and overpressure. An evaluation was conducted for the visual shape of the free jet and the perceived erosion characteristics of the specimen by scanning electron microscopy (SEM).