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A 3D Simulation on Fluid Field at the Impact Zone of Abrasive Water Jet under Different Impact Angles

Having an insight on the fluid field in AWJ machining is of important significance but the direct observation and measurement can be hardly implemented. Thus a 3D simulation of the fluid field in AWJ has been undertaken using FLUENT 6.3. The pressure and velocity distribution results on the impacted surface under different impact angle conditions are acquired and analyzed. The influence of the impact angle on the characteristics such as the symmetry of the distribution, position of the maximum value and the stagnation effect is highly concerned. In addition, an experiment under the similar conditions of the simulation is conducted and the results are compared with that of the simulation.

An Experimental Research on Abrasive Water Jet Polishing of the Hard Brittle Ceramics

Abrasive water jet (AWJ) technology, due to its potential advantages, is a promising machining method for precision machining brittle materials. In this research, the AlN ceramics was polished using an AWJ machining system. A considerable processing quality has been achieved and a reduction up to 62% of the surface roughness has been obtained. Effects of different process parameters on the surface roughness of the polished workpiece were analyzed. Under the current conditions of the experiments, using a lower impact angle, smaller abrasives and a lower nozzle traverse speed may be appropriate for polishing AlN ceramics.

Experimental Study of the Ultrasonic Vibration-Assisted Abrasive Waterjet Micromachining the Quartz Glass

The ultrasonic vibration is used to enhance the capability of the abrasive water micromachining glass. And, the ultrasonic vibration is activated on the abrasive waterjet nozzle. The quality of the flow is improved, and the velocity of the abrasive is increased because of the addition of the ultrasonic energy. The relevant experimental results indicate that the erosion depth and the material volume removal of the glass are obviously increased when ultrasonic vibration is working. As for the influence of process parameters on the material removal of the glass such as vibration amplitude, system pressure, distance of the standoff, and abrasive size, the experimental results indicate that the system pressure and vibration contribute greatly to the glass material removal. Also, the erosion depth and the volume of material removal are increased with the increase in the vibration amplitude and system pressure. There are some uplifts found at the edge of erosion pit. Then, it can be inferred that the plastic method is an important material removal method during the machining process of ultrasonic vibration-assisted abrasive waterjet.

Experimental Investigation on the Material Removal of the Ultrasonic Vibration Assisted Abrasive Water Jet Machining Ceramics

The ultrasonic vibration activated in the abrasive water jet nozzle is used to enhance the capability of the abrasive water jet machinery. The experiment devices of the ultrasonic vibration assisted abrasive water jet are established; they are composed of the ultrasonic vibration producing device, the abrasive supplying device, the abrasive water jet nozzle, the water jet intensifier pump, and so on. And the effect of process parameters such as the vibration amplitude, the system working pressure, the stand-off, and the abrasive diameter on the ceramics material removal is studied. The experimental result indicates that the depth and the volume removal are increased when the ultrasonic vibration is added on abrasive water jet. With the increase of vibration amplitude, the depth and the volume of material removal are also increased. The other parameters of the ultrasonic vibration assisted abrasive water jet also have an important role in the improvement of ceramic material erosion efficiency.