Papers by Keyword: Abrasive Waterjet Milling

Abstract: The profile of a single-pass milling can be assumed as a cosine curve. Therefore, the maximal depth model for single-pass milling is established which indicates the quantitative relationship between the AWJ single-pass milling depth and the milling parameters. The depth model of milled surface, which shows the effect of water pressure, standoff distance, lateral spacing, abrasive flow rate and the properties of the material on the AWJ milling depth, is established based on the maximal depth model for single-pass milling. The derived model is assessed by AWJ milling experiments. The results show that the milling depth increases with an increase in water pressure and standoff distance, and decreases with an increase in lateral spacing and traverse speed. The theoretical milling depth predicted by the mathematical model is good agreement with the experimental result.

Abstract: An experimental investigation of the material removal process in abrasive waterjet (AWJ) milling is presented. The experiment was conducted on an amorphous glass for milling channels of controlled depth. It is found that the channels are formed through four different zones, i.e. an opening zone, a steady-cutting zone, a unsteady-cutting zone and a finishing zone. The effect of process parameters on the channel formation process and the major milling performance measures (depth of cut and material removal rate) is then discussed. It is found that AWJ milling is a viable process for machining applications and the milling performance can be reasonably controlled through the selection of process parameters.

Abstract: In this paper, an experimental evaluation of the surface microstructural integrity of Si3N4 ceramics milled with abrasive waterjet was studied. The results show that the surface residual stress resulting from abrasive waterjet milling process for ceramics is compressive, and the compressive residual stress ranges from negative 203MPa to negative 19.6MPa. The results also show that the water pressure, the standoff distance, nozzle traverse speed and the lateral spacing have strong effects on the surface residual stress. The results also show that there is some enhancement in the hardness of AWJ milling surface, and it is affected by milling process parameters. The micro-topography of the milled surface cross section shows that there is a thin deteriorative layer in milled layer, in which no obvious crack is observed. Since the surface residual stress is compressive and the surface hardness increases, the milled surface deteriorative layer by AWJ could improve the surface quality.

Abstract: The machining performance of Al2O3 ceramics is studied by abrasive waterjet (AWJ) milling experiment. The machined surface characteristics and the effect of process parameters on machined surface quality are analyzed. The results showed that the nozzle traverse speed and traverse feed have a strong effect on the machined surface quality. The effect of process parameters on material volume removal rate and the milling depth is also researched. The results indicated that the material volume removal rate and the milling depth would be increased at the milling conditions of higher water pressure and bigger standoff distance. However, the milling depth will decrease at the milling conditions of higher traverse speed and higher traverse feed, and the material volume removal rate has a complex variation.

Abstract: The surface characteristics of Si3N4 ceramics milled with abrasive waterjet milling technology is studied. The milled surface characteristics and the effect of process parameters on milled surface roughness are analyzed. The results show that the milled surface roughness ranges between 0.55 and 1.1um at the milling conditions under consideration and is changed with the change of process parameters. The milled surface roughness will be significantly decreased at the milling conditions of lower water pressure and larger lateral spacing. The effect of nozzle traverse speed on milled surface roughness is complex, but a traverse speed of 1000mm/min is the optimum speed for AWJ milling Si3N4 ceramics. The milled surface roughness first decreases then increases with an enhancement of standoff distance from 10mm to 30mm, and it also significantly decreases with the increase in abrasive mesh. Therefore, the medium standoff distance of 20mm and finer abrasive are the optimum conditions for AWJ milling Si3N4 ceramics with the process parameters under consideration.